Private // practical // free

Free tools.

326 free privacy-first utilities for documents, data, media, developers and everyday work. Every tool runs in your browser. No account, upload or server processing is required.

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Showing all 326 tools

PDF

PDF Preflight & Compatibility Checker

Measure PDF structure, page geometry, fonts, images, encryption and metadata presence locally, separating hard evidence from bounded compatibility warnings.

Open tool PDF

Merge PDF

Merge PDFs in selected file and page order while preserving page objects.

Open tool PDF

Split PDF

Select bounded page ranges and export individual PDFs or one selected-pages PDF in a ZIP.

Open tool PDF

Secure PDF Redaction

Remove selected page content through disclosed full-page rasterization, pixel redaction and leak-gated PDF rebuilding.

Open tool PDF

PDF Redaction Leak Checker

Scan extracted text, raw objects, metadata and active features for masked redaction leak indicators.

Open tool PDF

PDF Privacy Scanner

Inspect PDF metadata, embedded or active features and optional sensitive terms without exposing their values.

Open tool PDF

PDF to JPG

Rasterize selected PDF pages to bounded JPEG files and independently verify every ZIP entry.

Open tool PDF

Images to PDF

Embed selected PNG or JPEG images as ordered PDF pages with explicit page sizing and margins.

Open tool PDF

Compress PDF to Exact Size

Target a maximum PDF byte size locally with bounded structural optimization, exact measurement and independent output reopening.

Open tool Images

Resize Image

Resize a raster image to exact bounded dimensions with explicit contain, cover or stretch behavior.

Open tool Images

Compress Image to Exact KB

Compress JPEG, PNG or WebP locally to an exact maximum file size. The output is decoded independently to confirm it really fits under your limit.

Open tool Images

Image Format Converter

Convert PNG, JPEG or WebP pixels to a selected browser-verified raster format.

Open tool Images

HEIC to JPG

Decode one HEIC or HEIF image locally and export a fresh JPEG file.

Open tool Images

Remove Image Metadata

Flatten PNG, JPEG or WebP pixels into a fresh image without source metadata segments.

Open tool Images

Remove Photo GPS Location

Detect a JPEG GPS directory when present and export a fresh pixel-only copy without EXIF location data.

Open tool Images

Stitch Screenshots

Join two to twenty images vertically or horizontally with an explicit gap and background.

Open tool Images

Panorama Carousel Splitter

Split one panorama into ordered PNG parts with an explicit axis and bounded overlap.

Open tool Images

Favicon Generator

Generate a verified ICO, standard PNG icon sizes and copy-ready link markup from one image.

Open tool Images

Responsive Image Generator

Generate selected WebP and PNG fallback widths plus copy-ready picture markup in one archive.

Open tool Images

SVG Sanitizer

Rebuild a strict passive SVG subset while rejecting scripts, external references and active constructs.

Open tool Video

Video Preflight & Upload Checker

Inspect actual container, stream, codec, duration, dimension, frame-rate, audio, color and seekability facts locally, then compare them with explicit dated.

Open tool Audio

Compress Audio to Exact Size

Fit PCM WAV audio under a maximum byte size by bounded channel and sample-rate correction while preserving duration.

Open tool Audio

Trim Audio

Trim PCM WAV audio to bounded start and end times with sample-frame accurate reported boundaries.

Open tool Audio

Merge Audio

Concatenate two to twenty PCM WAV files after explicit sample-rate and channel normalization.

Open tool Audio

Normalize Audio Loudness

Normalize PCM WAV to an explicit peak or transparent RMS target without clipping.

Open tool Audio

Waveform Image Generator

Render a transparent bounded PNG waveform from decoded PCM WAV samples.

Open tool Social & Creator

Social Export Pack

Create independently cropped image or video variants for dated social placement profiles, preview advisory safe zones, and download a verified ZIP with human.

Open tool Social & Creator

Social Media File Preflight

Check a local image or video against dated official-source placement profiles and explain every result.

Open tool Social & Creator

Social Safe Zone Preview

Overlay an advisory placement UI safe zone on a local image without changing the source.

Open tool Social & Creator

Instagram Carousel Maker

Build an ordered ZIP of independently reopened 4:5 Instagram carousel slides from local images.

Open tool Social & Creator

YouTube Shorts Checker

Check vertical orientation, three-minute duration, 1080p resolution, audio and decode compatibility using current YouTube guidance.

Open tool Social & Creator

YouTube Thumbnail Maker

Create a 3840×2160 PNG thumbnail from a local image with optional bounded text.

Open tool Social & Creator

LinkedIn PDF Carousel Maker

Turn ordered local images into a flattened equal-size PDF below LinkedIn document limits.

Open tool Office, Documents & E-books

Office Privacy Scanner

Inspect bounded DOCX, XLSX and PPTX packages for metadata, comments, revisions, hidden content, external links, macros and embedded files without executing.

Open tool Office, Documents & E-books

Hidden Excel Content Scanner

Inspect hidden sheets, rows, columns and cached formulas without exposing cell values.

Open tool Office, Documents & E-books

Excel to CSV

Extract a selected XLSX worksheet to CSV locally without executing formulas.

Open tool Office, Documents & E-books

DOCX to Text

Extract DOCX paragraphs and table text locally as layout-free plain text.

Open tool Data & Spreadsheets

Data File Preflight

Inspect encoding, delimiter, schema, row count, malformed records, nulls and size before processing. Processing is local and independently checked.

Open tool Data & Spreadsheets

Large CSV Viewer

Stream, search and page through a CSV locally while keeping every value as text, then independently rescan the source before downloading a bounded JSON report.

Open tool Data & Spreadsheets

CSV Cleaner

Review detected delimiter and UTF-8/UTF-16 encoding, then repair whitespace, blank rows, quoting and newlines to normalized UTF-8 CSV.

Open tool Data & Spreadsheets

CSV Encoding Converter

Detect likely encoding and export UTF-8 or another supported encoding. Processing is local and independently checked.

Open tool Data & Spreadsheets

CSV Delimiter Converter

Convert comma, semicolon, tab, pipe or custom separators safely. Processing is local and independently checked.

Open tool Data & Spreadsheets

Remove Duplicate CSV Rows

Deduplicate by selected key columns with explicit first, last or counted aggregate policy.

Open tool Data & Spreadsheets

Merge CSV Files

Append selected CSV files with reviewable union-by-name schema reconciliation or strict exact-schema mode.

Open tool Data & Spreadsheets

Split CSV

Split CSV by row count, target file size, column value or requested part count into a bounded schema-preserving ZIP.

Open tool Data & Spreadsheets

Select or Remove CSV Columns

Reorder, rename, keep or drop columns. Processing is local and independently checked.

Open tool Data & Spreadsheets

CSV Validator

Validate row width, types, required fields, patterns, ranges and uniqueness. Processing is local and independently checked.

Open tool Data & Spreadsheets

CSV to JSON

Export array, object, keyed or NDJSON formats. Processing is local and independently checked.

Open tool Data & Spreadsheets

JSON to CSV

Flatten selected paths and export tabular rows. Processing is local and independently checked.

Open tool Data & Spreadsheets

CSV to Parquet

Convert bounded CSV to Parquet with reviewable strict inference or all-text schema and Snappy or uncompressed output.

Open tool Data & Spreadsheets

Parquet Viewer

Inspect local Parquet metadata and run bounded column projection and equality-filter queries without SQL or remote ranges.

Open tool Data & Spreadsheets

JSON Viewer

Parse, fold, search and navigate JSON. Processing is local and independently checked.

Open tool Data & Spreadsheets

JSON Formatter & Minifier

Pretty-print or minify valid JSON with exact error positions. Processing is local and independently checked.

Open tool Data & Spreadsheets

JSON Compare

Compare structures with configurable array matching. Processing is local and independently checked.

Open tool Data & Spreadsheets

JSON Schema Validator

Validate against pasted or uploaded schemas. Processing is local and independently checked.

Open tool Data & Spreadsheets

YAML to JSON

Parse safe YAML without executing custom tags. Processing is local and independently checked.

Open tool Data & Spreadsheets

JSON to YAML

Convert valid JSON with style controls. Processing is local and independently checked.

Open tool Data & Spreadsheets

YAML Validator

Report syntax, duplicate keys and unsafe constructs. Processing is local and independently checked.

Open tool Data & Spreadsheets

SQLite Browser Viewer

Inspect local SQLite tables, indexes, views and bounded data through generated read-only queries with no user SQL field.

Open tool Data & Spreadsheets

Data PII Detector

Find likely emails, phones, IDs, IPs and a configurable literal pattern while reporting only masked classes and counts.

Open tool Data & Spreadsheets

Data Anonymizer

Mask, hash, tokenize, generalize or synthesize selected CSV columns locally, then independently reparse and verify every transformed cell before download.

Open tool Privacy & Safe Sharing

SafeShare File Privacy Scanner

Run signature-selected PDF, PNG or JPEG disclosure detectors, review every supported removal, and download only a same-format copy that independently reopens.

Open tool Privacy & Safe Sharing

Universal Metadata Cleaner

Remove reviewed metadata classes from JPEG, PNG and PDF copies and rescan the output.

Open tool Privacy & Safe Sharing

Screenshot Redaction Leak Checker

Measure raster transparency and redaction-like regions while requiring manual visual review.

Open tool Privacy & Safe Sharing

URL Tracking Parameter Cleaner

Remove known and explicitly selected tracking parameters without contacting any URL.

Open tool Privacy & Safe Sharing

HAR Privacy Cleaner

Remove common secrets from a HAR network log locally, then independently reparse and rescan the cleaned file before download.

Open tool Privacy & Safe Sharing

Log Sanitizer

Replace bounded secret, identity and custom defensive patterns and independently rescan text.

Open tool Privacy & Safe Sharing

Source Archive Secret Scanner

Scan bounded text entries in a safe local ZIP without executing files or validating credentials.

Open tool Privacy & Safe Sharing

API Key Scanner

Report masked credential and high-entropy candidates without validation or remote lookup.

Open tool Privacy & Safe Sharing

Local File Encryptor

Encrypt one or more files with authenticated encryption and a user passphrase. Uses explicit bounds and independent local verification.

Open tool Privacy & Safe Sharing

Local File Decryptor

Decrypt files produced by the site after user supplies the correct passphrase. Uses explicit bounds and independent local verification.

Open tool Privacy & Safe Sharing

Password Generator

Generate passwords or passphrases locally using cryptographic randomness. Uses explicit bounds and independent local verification.

Open tool Privacy & Safe Sharing

Password Strength Checker

Estimate strength locally without transmitting the password or claiming certainty. Uses explicit bounds and independent local verification.

Open tool Privacy & Safe Sharing

File & Text Hash Generator

Generate SHA-256, SHA-384, SHA-512 and other approved available digests. Uses explicit bounds and independent local verification.

Open tool Privacy & Safe Sharing

Checksum Verifier

Compare a file digest to a pasted expected value. Uses explicit bounds and independent local verification.

Open tool Privacy & Safe Sharing

Subresource Integrity Generator

Generate browser-compatible integrity attributes for local assets. Uses explicit bounds and independent local verification.

Open tool Privacy & Safe Sharing

JWT Inspector

Decode header and payload locally, display time claims and never imply signature validity without a key. Uses explicit bounds and independent local.

Open tool Developer & Web Utilities

JSON Formatter

Format, minify and sort bounded JSON without uploading it.

Open tool Developer & Web Utilities

YAML / JSON Converter

Convert data-only YAML and JSON locally with aliases and custom tags disabled.

Open tool Developer & Web Utilities

Regular Expression Tester

Test a bounded regular expression in a disposable worker with match and capture positions.

Open tool Developer & Web Utilities

Base64 Encoder/Decoder

Encode or decode bounded text and files locally without interpreting the decoded content.

Open tool Developer & Web Utilities

URL Parser

Break a pasted URL into bounded components without opening it or exposing secret values.

Open tool Developer & Web Utilities

OpenAPI Validator

Validate bounded OpenAPI 3 structure and local references without sending described requests.

Open tool Developer & Web Utilities

HAR Viewer

Inspect sanitized HAR request, timing and size facts locally without replaying traffic.

Open tool Developer & Web Utilities

Source Map Inspector

Inspect Source Map v3 mappings, paths and embedded-content facts locally without executing source code.

Open tool Files, Archives & Folders

Create ZIP Archive

Package selected local files into a bounded ZIP and independently reopen every entry.

Open tool Files, Archives & Folders

Extract ZIP Archive

Preflight a ZIP and expose bounded safe entries as separate local downloads.

Open tool Files, Archives & Folders

ZIP Bomb Risk Checker

Inspect ZIP central-directory metadata locally for dangerous expansion ratios, entry counts, paths and nesting without inflating payloads.

Open tool Files, Archives & Folders

Duplicate File Finder

Group selected files by exact size and SHA-256 without uploading or modifying them.

Open tool Files, Archives & Folders

Batch File Renamer

Preview and confirm deterministic collision-safe renamed copies in a ZIP.

Open tool Fonts, Design & Accessibility

Font Inspector

Inspect bounded TTF and OTF tables, metrics, variation axes and licensing metadata without loading font content.

Open tool Fonts, Design & Accessibility

WCAG Color Contrast Checker

Calculate WCAG 2.x relative luminance, contrast ratios and applicable thresholds locally.

Open tool QR Codes & Barcodes

QR Code Generator

Generate a bounded QR symbol locally and independently decode it back to the exact UTF-8 payload.

Open tool QR Codes & Barcodes

QR Code Reader

Decode a bounded uploaded image or explicitly captured camera frame locally without following its payload.

Open tool Text & Language

Word & Character Counter

Count UTF-8 bytes, Unicode code points, grapheme clusters, words, sentences, paragraphs and lines locally with an explicit locale and method.

Open tool Text & Language

Text Case Converter

Convert UTF-8 text to lower, upper, title, sentence, camel, Pascal, kebab, snake or constant case locally with explicit locale-aware behavior.

Open tool Text & Language

Remove Duplicate Lines

Remove duplicate UTF-8 lines locally while preserving first occurrence order and making trim, case and line-ending policies explicit.

Open tool Text & Language

Subtitle File Editor

Validate, shift, rescale, merge, split and reflow SRT, WebVTT or constrained ASS captions locally, then export independently reparsed soft subtitles.

Open tool Unit Converters & Measurement

Length Converter

Convert metric, imperial, nautical and astronomical length units with exact formulas. Uses explicit units, formulas and rounding locally.

Open tool Unit Converters & Measurement

Area Converter

Convert square metric, imperial, land and survey area units. Uses explicit units, formulas and rounding locally.

Open tool Unit Converters & Measurement

Volume Converter

Convert metric, imperial, US customary and common household volume units. Uses explicit units, formulas and rounding locally.

Open tool Unit Converters & Measurement

Mass & Weight Converter

Convert mass and weight units from micrograms through tonnes, pounds, stones and carats. Uses explicit units, formulas and rounding locally.

Open tool Unit Converters & Measurement

Temperature Converter

Convert Celsius, Fahrenheit, Kelvin and Rankine with formula steps. Uses explicit units, formulas and rounding locally.

Open tool Unit Converters & Measurement

Speed Converter

Convert km/h, mph, m/s, knots, pace and Mach where assumptions are explicit. Uses explicit units, formulas and rounding locally.

Open tool Unit Converters & Measurement

Time Unit Converter

Convert nanoseconds through years using clearly stated average-unit assumptions. Uses explicit units, formulas and rounding locally.

Open tool Unit Converters & Measurement

Angle Converter

Convert degrees, radians, gradians, turns and arc units. Uses explicit units, formulas and rounding locally.

Open tool Unit Converters & Measurement

Pressure Converter

Convert pascals, bar, psi, atmospheres, torr and water-column units. Uses explicit units, formulas and rounding locally.

Open tool Unit Converters & Measurement

Energy Converter

Convert joules, calories, watt-hours, BTU, electronvolts and related energy units. Uses explicit units, formulas and rounding locally.

Open tool Unit Converters & Measurement

Power Converter

Convert watts, horsepower, BTU per hour and other power units. Uses explicit units, formulas and rounding locally.

Open tool Unit Converters & Measurement

Frequency Converter

Convert hertz and metric frequency multiples, RPM and cycles per time. Uses explicit units, formulas and rounding locally.

Open tool Unit Converters & Measurement

Data Storage Converter

Convert decimal and binary bytes, bits, KB, KiB, MB, MiB, GB and larger units. Uses explicit units, formulas and rounding locally.

Open tool Unit Converters & Measurement

Data Transfer Rate Converter

Convert bit/s, byte/s and decimal or binary network throughput units. Uses explicit units, formulas and rounding locally.

Open tool Unit Converters & Measurement

Download Time Calculator

Estimate transfer time from file size, throughput and protocol-overhead assumptions. Uses explicit units, formulas and rounding locally.

Open tool Unit Converters & Measurement

Upload Time Calculator

Estimate upload duration from file size and measured or entered uplink speed. Uses explicit units, formulas and rounding locally.

Open tool Unit Converters & Measurement

Aspect Ratio Calculator

Calculate, simplify and apply aspect ratios to missing dimensions. Uses explicit local formulas and independent verification.

Open tool Math & Statistics

Scientific Calculator

Evaluate standard arithmetic, trigonometric, logarithmic and exponential expressions locally. Shows the formula and independently checks the result.

Open tool Math & Statistics

Percentage Calculator

Solve percentage-of, what-percent and reverse-percentage problems with shown formulas. Shows the formula and independently checks the result.

Open tool Math & Statistics

Percentage Change Calculator

Calculate increase or decrease between two values and handle sign changes explicitly. Shows the formula and independently checks the result.

Open tool Math & Statistics

Percentage Difference Calculator

Calculate symmetric percentage difference between two values. Shows the formula and independently checks the result.

Open tool Math & Statistics

Fraction Calculator

Add, subtract, multiply and divide fractions with simplified steps. Shows the formula and independently checks the result.

Open tool Math & Statistics

Mixed Number Calculator

Calculate with mixed numbers and convert between improper fractions and mixed form. Shows the formula and independently checks the result.

Open tool Math & Statistics

Decimal to Fraction Converter

Convert terminating or repeating decimals to reduced fractions. Shows the formula and independently checks the result.

Open tool Math & Statistics

Fraction / Decimal / Percent Converter

Convert among fraction, decimal and percentage representations. Shows the formula and independently checks the result.

Open tool Math & Statistics

Ratio Calculator

Simplify ratios, find missing terms and scale quantities. Shows the formula and independently checks the result.

Open tool Math & Statistics

Proportion Calculator

Solve one unknown in equivalent ratios and show cross-multiplication. Shows the formula and independently checks the result.

Open tool Math & Statistics

Rule of Three Calculator

Solve direct and inverse proportionality problems. Shows the formula and independently checks the result.

Open tool Math & Statistics

Average Calculator

Calculate arithmetic mean, count, sum and optional trimmed mean. Shows the formula and independently checks the result.

Open tool Math & Statistics

Weighted Average Calculator

Calculate weighted means and expose each contribution. Shows the formula and independently checks the result.

Open tool Math & Statistics

Median, Mode & Range Calculator

Calculate median, modes, range and sorted data from pasted values. Shows the formula and independently checks the result.

Open tool Math & Statistics

Random Number Generator

Generate integers or decimals with crypto randomness or a reproducible seed. Uses explicit bounds and independent local verification.

Open tool Math & Statistics

Distance Between Two Points Calculator

Calculate 2D or 3D Euclidean distance. Uses explicit local formulas and independent verification.

Open tool Math & Statistics

Midpoint Calculator

Calcute midpoint coordinates in two or three dimensions. Uses explicit local formulas and independent verification.

Open tool Math & Statistics

Slope Calculator

Calculate slope, angle and line equation from points. Uses explicit local formulas and independent verification.

Open tool Math & Statistics

Line Equation Calculator

Convert among slope-intercept, point-slope and standard line forms. Uses explicit local formulas and independent verification.

Open tool Math & Statistics

Pythagorean Theorem Calculator

Solve the missing side of a right triangle and verify inputs. Uses explicit local formulas and independent verification.

Open tool Math & Statistics

Triangle Calculator

Solve valid triangles from supported side and angle combinations. Uses explicit local formulas and independent verification.

Open tool Math & Statistics

Right Triangle Calculator

Calculate sides, angles, area and perimeter for right triangles. Uses explicit local formulas and independent verification.

Open tool Math & Statistics

Circle Calculator

Calculate radius, diameter, circumference and area. Uses explicit local formulas and independent verification.

Open tool Math & Statistics

Rectangle Calculator

Calculate area, perimeter and diagonal. Uses explicit local formulas and independent verification.

Open tool Math & Statistics

Sphere Calculator

Calculate radius, diameter, surface area and volume. Uses explicit local formulas and independent verification.

Open tool Math & Statistics

Cylinder Calculator

Calculate volume, lateral area and total surface area. Uses explicit local formulas and independent verification.

Open tool Math & Statistics

Rectangular Prism Calculator

Calculate volume, surface area and space diagonal. Uses explicit local formulas and independent verification.

Open tool Finance, Business & E-commerce

Mortgage Calculator

Calculate principal-and-interest payments, amortization and total interest from your own terms. Runs locally and shows every assumption behind the result.

Open tool Finance, Business & E-commerce

Mortgage Extra Payment Calculator

Compare payoff time and interest with recurring or one-off overpayments. The bounded local result records assumptions and is independently recomputed.

Open tool Finance, Business & E-commerce

Loan Calculator

Calculate payment, total interest and amortization for fixed-rate installment loans. The bounded local result records assumptions and is independently.

Open tool Finance, Business & E-commerce

Loan Payment Calculator

Solve payment from amount, rate and term or solve another missing variable. The bounded local result records assumptions and is independently recomputed.

Open tool Finance, Business & E-commerce

Loan Amortization Calculator

Generate a verified amortization schedule with optional extra payments. The bounded local result records assumptions and is independently recomputed.

Open tool Finance, Business & E-commerce

Auto Loan Calculator

Estimate vehicle finance payments including deposit, trade-in, fees and taxes. Runs locally and shows every assumption behind the result.

Open tool Finance, Business & E-commerce

Simple Interest Calculator

Calculate principal, rate, time, interest or final balance. The bounded local result records assumptions and is independently recomputed.

Open tool Finance, Business & E-commerce

Compound Interest Calculator

Calculate compound growth with contributions and configurable compounding frequency. The bounded local result records assumptions and is independently.

Open tool Finance, Business & E-commerce

APR / APY Converter

Convert nominal APR and effective APY under a chosen compounding schedule. The bounded local result records assumptions and is independently recomputed.

Open tool Finance, Business & E-commerce

Savings Goal Calculator

Calculate required recurring contribution or time to reach a target. The bounded local result records assumptions and is independently recomputed.

Open tool Finance, Business & E-commerce

Savings Growth Calculator

Project savings with deposits, withdrawals, interest and inflation assumptions. The bounded local result records assumptions and is independently recomputed.

Open tool Finance, Business & E-commerce

Investment Return Calculator

Calculate absolute, percentage, annualized and money-weighted returns from your cash flows. Runs locally and shows every assumption behind the result.

Open tool Finance, Business & E-commerce

Future Value Calculator

Calculate future value of a lump sum or annuity. The bounded local result records assumptions and is independently recomputed.

Open tool Finance, Business & E-commerce

Present Value Calculator

Discount future cash flows to present value. The bounded local result records assumptions and is independently recomputed.

Open tool Finance, Business & E-commerce

Net Present Value Calculator

Calculate NPV from irregular or regular cash flows and a discount rate. The bounded local result records assumptions and is independently recomputed.

Open tool Finance, Business & E-commerce

Inflation Impact Calculator

Project purchasing power using a user-entered inflation assumption. The bounded local result records assumptions and is independently recomputed.

Open tool Finance, Business & E-commerce

Debt Payoff Calculator

Compare payoff dates and interest under minimum, snowball and avalanche strategies. The bounded local result records assumptions and is independently.

Open tool Finance, Business & E-commerce

Credit Card Payoff Calculator

Calculate payoff time, required payment and total interest. The bounded local result records assumptions and is independently recomputed.

Open tool Finance, Business & E-commerce

Debt-to-Income Ratio Calculator

Calculate front-end and back-end debt-to-income ratios. The bounded local result records assumptions and is independently recomputed.

Open tool Finance, Business & E-commerce

Profit Margin Calculator

Calculate gross margin, markup, profit and selling price from any two known values. Uses explicit generic assumptions and independent local verification.

Open tool Finance, Business & E-commerce

Markup Calculator

Calculate markup percentage, margin and price from cost and selling price. Uses explicit generic assumptions and independent local verification.

Open tool Finance, Business & E-commerce

Break-even Calculator

Calculate break-even units and revenue from fixed costs, price and variable cost. Uses explicit generic assumptions and independent local verification.

Open tool Finance, Business & E-commerce

Product Pricing Calculator

Build a selling price from cost, target margin, fees, discounts and taxes. Uses explicit generic assumptions and independent local verification.

Open tool Finance, Business & E-commerce

Discount Calculator

Calculate final price, amount saved and reverse discount. Uses explicit generic assumptions and independent local verification.

Open tool Finance, Business & E-commerce

VAT Calculator

Add or remove VAT using a user-entered or versioned jurisdiction profile. Uses explicit generic assumptions and independent local verification.

Open tool Finance, Business & E-commerce

Reverse VAT Calculator

Extract net amount and VAT from a gross total. Uses explicit generic assumptions and independent local verification.

Open tool Finance, Business & E-commerce

Unit Price Calculator

Compare price per mass, volume, length, area or count. Uses explicit generic assumptions and independent local verification.

Open tool Finance, Business & E-commerce

Payment Processor Fee Calculator

Calculate gross-to-net or required gross from percentage and fixed fees. Uses explicit generic assumptions and independent local verification.

Open tool Finance, Business & E-commerce

ROI Calculator

Calculate return on investment, gain, cost and annualized ROI. Uses explicit generic assumptions and independent local verification.

Open tool Finance, Business & E-commerce

ROAS Calculator

Calculate return on ad spend and break-even thresholds. Uses explicit generic assumptions and independent local verification.

Open tool Finance, Business & E-commerce

CPM Calculator

Solve cost, impressions or cost per thousand. Uses explicit generic assumptions and independent local verification.

Open tool Finance, Business & E-commerce

CPC Calculator

Solve spend, clicks or cost per click. Uses explicit generic assumptions and independent local verification.

Open tool Finance, Business & E-commerce

CTR Calculator

Calculate click-through rate from clicks and impressions. Uses explicit generic assumptions and independent local verification.

Open tool Finance, Business & E-commerce

Invoice Generator

Create a local printable invoice with line items, taxes, terms and optional branding. Uses explicit generic assumptions and independent local verification.

Open tool Finance, Business & E-commerce

Quote / Estimate Generator

Create a printable quotation or estimate without storing customer data. Uses explicit generic assumptions and independent local verification.

Open tool Date, Time & Productivity

Age Calculator

Calculate exact age in years, months, days and total units from two dates. Uses explicit date-only Gregorian rules and independent local verification.

Open tool Date, Time & Productivity

Age Difference Calculator

Calculate exact age gap between two birth dates. Uses explicit date-only Gregorian rules and independent local verification.

Open tool Date, Time & Productivity

Days Between Dates Calculator

Calculate calendar days, weekdays, weeks, months and years between dates. Uses explicit date-only Gregorian rules and independent local verification.

Open tool Date, Time & Productivity

Add or Subtract Days from a Date

Add or subtract calendar units with explicit month-end behavior. Uses explicit date-only Gregorian rules and independent local verification.

Open tool Date, Time & Productivity

Business Days Calculator

Count workdays between dates using selectable weekends and imported holiday lists. Uses explicit date-only Gregorian rules and independent local verification.

Open tool Date, Time & Productivity

Workday Date Calculator

Find a date after or before a given number of working days. Uses explicit date-only Gregorian rules and independent local verification.

Open tool Date, Time & Productivity

Deadline Calculator

Calculate deadlines from start date, duration, workdays and custom blackout dates. Uses explicit date-only Gregorian rules and independent local verification.

Open tool Date, Time & Productivity

Day of Week Calculator

Find the weekday for a valid Gregorian date. Uses explicit date-only Gregorian rules and independent local verification.

Open tool Date, Time & Productivity

Week Number Calculator

Calculate ISO week date and configurable week-number conventions. Uses explicit date-only Gregorian rules and independent local verification.

Open tool Date, Time & Productivity

Birthday Countdown

Count down to the next birthday and show weekday. Uses explicit date-only Gregorian rules and independent local verification.

Open tool Date, Time & Productivity

Time Duration Calculator

Add, subtract and normalize hours, minutes, seconds and milliseconds. Uses explicit date-only Gregorian rules and independent local verification.

Open tool Date, Time & Productivity

Hours & Minutes Calculator

Calculate time values without decimal-hour mistakes. Uses explicit date-only Gregorian rules and independent local verification.

Open tool Education & Study

Grade Calculator

Calculate weighted or points-based course grades from assignments and categories. Uses explicit user-supplied rules and independent local verification.

Open tool Education & Study

Final Grade Calculator

Calculate the score required on a final exam to reach a target course grade. Uses explicit user-supplied rules and independent local verification.

Open tool Education & Study

Test Grade Calculator

Convert correct answers into percentage and configurable letter grades. Uses explicit user-supplied rules and independent local verification.

Open tool Education & Study

GPA Calculator

Calculate term and cumulative GPA using a configurable grading scale. Uses explicit user-supplied rules and independent local verification.

Open tool Education & Study

Attendance Percentage Calculator

Calculate attendance rate and remaining allowable absences from user-defined requirements. Uses explicit user-supplied rules and independent local verification.

Open tool Education & Study

Exam Score Target Calculator

Calculate points or percentage needed to pass or reach a target. Uses explicit user-supplied rules and independent local verification.

Open tool Education & Study

Exam Study Plan Generator

Create a day-by-day revision plan from topics, confidence and exam dates. Uses explicit user-supplied rules and independent local verification.

Open tool Education & Study

Assignment Planner

Break an assignment into milestones based on due date and estimated effort. Uses explicit user-supplied rules and independent local verification.

Open tool Writing, Email & Communication

Title Case Converter

Apply selectable English title-capitalization styles and show changed words. Uses explicit Unicode rules and independent local verification.

Open tool Writing, Email & Communication

Sentence Counter

Count sentences with locale-aware segmentation and ambiguous-boundary warnings. Uses explicit Unicode rules and independent local verification.

Open tool Writing, Email & Communication

Readability Score Calculator

Calculate multiple readability metrics and expose formula limitations. Uses explicit Unicode rules and independent local verification.

Open tool Writing, Email & Communication

Flesch-Kincaid Calculator

Calculate reading ease and grade-level estimates for English text. Uses explicit Unicode rules and independent local verification.

Open tool Writing, Email & Communication

Repeated Word Finder

Find nearby or excessive repeated words with configurable distance. Uses explicit Unicode rules and independent local verification.

Open tool Writing, Email & Communication

Filler Word Counter

Count configurable filler words in prose or transcripts. Uses explicit Unicode rules and independent local verification.

Open tool Writing, Email & Communication

Sentence Length Analyzer

Visualize sentence-length distribution and flag extreme outliers. Uses explicit Unicode rules and independent local verification.

Open tool Writing, Email & Communication

Keyword Density Calculator

Calculate term and phrase frequency without presenting density as a ranking guarantee. Uses explicit Unicode rules and independent local verification.

Open tool SEO, Webmaster & Marketing

SEO Title Checker

Check title length, pixel-width estimate, uniqueness within an imported list and likely truncation. Uses passive local parsing and independent verification.

Open tool SEO, Webmaster & Marketing

Meta Description Checker

Check length, pixel-width estimate and duplicates in a pasted or imported set. Uses passive local parsing and independent verification.

Open tool SEO, Webmaster & Marketing

SERP Pixel Width Checker

Estimate desktop and mobile title or description width using configurable font metrics. Uses passive local parsing and independent verification.

Open tool SEO, Webmaster & Marketing

Google Snippet Preview

Preview title, URL, description and optional rich-result elements without claiming exact rendering. Uses passive local parsing and independent verification.

Open tool SEO, Webmaster & Marketing

Heading Structure Checker

Extract H1–H6 hierarchy and flag missing, duplicate or skipped levels. Uses passive local parsing and independent verification.

Open tool SEO, Webmaster & Marketing

Canonical Tag Checker

Parse canonical declarations and compare normalized source and target URLs. Uses passive local parsing and independent verification.

Open tool SEO, Webmaster & Marketing

Robots Meta Tag Checker

Parse robots directives and highlight conflicting or unsupported combinations. Uses passive local parsing and independent verification.

Open tool SEO, Webmaster & Marketing

Robots.txt Validator

Validate syntax, grouping and sitemap directives in a robots.txt file. Uses passive local parsing and independent verification.

Open tool SEO, Webmaster & Marketing

UTM Campaign URL Builder

Build consistently encoded UTM URLs with configurable naming rules. Uses passive local parsing and independent verification.

Open tool SEO, Webmaster & Marketing

XML Sitemap Generator from URL List

Build a standards-compliant sitemap from pasted or imported URLs. Uses passive local parsing and independent verification.

Open tool SEO, Webmaster & Marketing

Keyword List Cleaner

Normalize, trim, deduplicate and sort keyword lists. Uses passive local parsing and independent verification.

Open tool SEO, Webmaster & Marketing

FAQ Schema Generator

Generate valid FAQPage JSON-LD from user-entered questions; warn about eligibility limits. Uses passive local parsing and independent verification.

Open tool SEO, Webmaster & Marketing

Open Graph Tag Checker

Parse and preview Open Graph tags from pasted HTML. Uses passive local parsing and independent verification.

Open tool SEO, Webmaster & Marketing

Image Alt Text Auditor

Extract image alt attributes and flag missing, empty or filename-like text for review. Uses passive local parsing and independent verification.

Open tool Networking, Domains & Internet

IPv4 Subnet Calculator

Calculate network, broadcast, host range, masks and address counts from IPv4 CIDR. Uses exact local arithmetic and independent verification.

Open tool Networking, Domains & Internet

CIDR Calculator

Convert prefix length, subnet mask, wildcard mask and address counts. Uses exact local arithmetic and independent verification.

Open tool Networking, Domains & Internet

Subnet Mask Converter

Convert dotted-decimal masks, prefixes, binary masks and wildcard masks. Uses exact local arithmetic and independent verification.

Open tool Networking, Domains & Internet

IP Range Calculator

Calculate inclusive IPv4 ranges and summarizehem as CIDR blocks. Uses exact local arithmetic and independent verification.

Open tool Networking, Domains & Internet

IP Range to CIDR Converter

Convert start/end IPv4 addresses into the minimal CIDR set. Uses exact local arithmetic and independent verification.

Open tool Networking, Domains & Internet

IPv6 Expand / Compress Tool

Normalize IPv6 addresses and validate embedded IPv4 forms. Uses exact local arithmetic and independent verification.

Open tool Networking, Domains & Internet

IP Address Decimal / Binary / Hex Converter

Convert IPv4 addresses among dotted, integer, binary and hexadecimal forms. Uses exact local arithmetic and independent verification.

Open tool Networking, Domains & Internet

Network & Broadcast Address Calculator

Calculate network and broadcast addresses from IP and mask. Uses exact local arithmetic and independent verification.

Open tool Home, Construction & DIY

Square Footage Calculator

Calculate total area from multiple rectangular, triangular, circular or custom sections. Uses local geometry and independent verification.

Open tool Home, Construction & DIY

Room Area Calculator

Calculate floor and wall areas while subtracting openings. Uses local geometry and independent verification.

Open tool Home, Construction & DIY

Paint Calculator

Estimate paint volume from surfaces, coats and user-entered coverage. Uses local geometry and independent verification.

Open tool Home, Construction & DIY

Wallpaper Roll Calculator

Estimate rolls from wall dimensions, repeat, roll size and waste. Uses local geometry and independent verification.

Open tool Home, Construction & DIY

Tile Calculator

Estimate tile count, boxes, cuts and waste from area and tile size. Uses local geometry and independent verification.

Open tool Home, Construction & DIY

Flooring Calculator

Estimate planks, packs, waste and cost for rectangular or multi-room floors. Uses local geometry and independent verification.

Open tool Home, Construction & DIY

Carpet Calculator

Estimate carpet area, roll layout, waste and cost. Uses local geometry and independent verification.

Open tool Home, Construction & DIY

Concrete Calculator

Calculate concrete volume and bags for slabs, footings, columns and steps. Uses local geometry and independent verification.

Open tool Home, Construction & DIY

Concrete Bag Calculator

Convert required wet volume into user-selected bag yields. Uses local geometry and independent verification.

Open tool Home, Construction & DIY

Brick Calculator

Estimate brick count, mortar joints, waste and wall area. Uses local geometry and independent verification.

Open tool Home, Construction & DIY

Concrete Block Calculator

Estimate block count and mortar from wall and unit dimensions. Uses local nominal formulas and independent verification.

Open tool Home, Construction & DIY

Drywall Calculator

Estimate boards, screws, joint compound and tape from wall/ceiling dimensions. Uses local nominal formulas and independent verification.

Open tool Home, Construction & DIY

Insulation Calculator

Estimate insulation area, rolls or batts and material cost. Uses local nominal formulas and independent verification.

Open tool Home, Construction & DIY

Roofing Calculator

Estimate roof area, pitch factor, shingles or sheets and waste. Uses local nominal formulas and independent verification.

Open tool Home, Construction & DIY

Roof Pitch Calculator

Convert rise/run, degrees and percentage slope. Uses local nominal formulas and independent verification.

Open tool Home, Construction & DIY

Deck Board Calculator

Estimate boards, gaps, joists, fasteners and waste. Uses local nominal formulas and independent verification.

Open tool Home, Construction & DIY

Post Hole Concrete Calculator

Estimate concrete volume or bags for cylindrical or square holes. Uses local nominal formulas and independent verification.

Open tool Home, Construction & DIY

Ramp Slope Calculator

Calculate rise, run, slope and angle with user-selected accessibility rules. Uses local nominal formulas and independent verification.

Open tool Home, Construction & DIY

Trench Volume Calculator

Calculate trench volume and backfill from length, width and depth. Uses local nominal formulas and independent verification.

Open tool Home, Construction & DIY

Paver Calculator

Estimate pavers, edge units, bedding sand and waste. Uses local nominal formulas and independent verification.

Open tool Food, Cooking & Household

Recipe Scaler

Scale ingredient quantities by servings, batch count or target yield. Uses local arithmetic and independent verification.

Open tool Food, Cooking & Household

Ingredient Cups to Grams Converter

Convert common ingredient volume and mass using a versioned density table and editable values. Uses local arithmetic and independent verification.

Open tool Food, Cooking & Household

Baker's Percentage Calculator

Calculate ingredient percentages relative to flour and rescale a formula. Uses local arithmetic and independent verification.

Open tool Food, Cooking & Household

Dough Hydration Calculator

Calculate true hydration including preferments and liquid ingredients. Uses local arithmetic and independent verification.

Open tool Food, Cooking & Household

Fresh / Active / Instant Yeast Converter

Convert yeast types using editable conversion assumptions. Uses local arithmetic and independent verification.

Open tool Food, Cooking & Household

Cake Pan Size Converter

Scale batter by pan area or volume across round, square and rectangular pans. Uses local arithmetic and independent verification.

Open tool Health, Fitness & Sports

Running Pace Calculator

Calculate pace, speed, time or distance in metric and imperial units. Uses transparent local arithmetic and independent verification.

Open tool Health, Fitness & Sports

Running Split Calculator

Generate even or negative splits for common or custom distances. Uses transparent local arithmetic and independent verification.

Open tool Health, Fitness & Sports

Marathon Pace Calculator

Calculate target pace and kilometer/mile splits for a marathon time. Uses local formulas and independent verification.

Open tool Health, Fitness & Sports

Half Marathon Pace Calculator

Calculate target pace and splits for a half-marathon time. Uses local formulas and independent verification.

Open tool Health, Fitness & Sports

5K Pace Calculator

Calculate time, pace and lap splits for 5 km. Uses local formulas and independent verification.

Open tool Health, Fitness & Sports

10K Pace Calculator

Calculate time, pace and splits for 10 km. Uses local formulas and independent verification.

Open tool Health, Fitness & Sports

Track Lap Split Calculator

Generate lap splits for arbitrary track length and target time. Uses local formulas and independent verification.

Open tool Health, Fitness & Sports

Walking Time Calculator

Estimate time from distance and entered pace or speed. Uses local formulas and independent verification.

Open tool Health, Fitness & Sports

Cycling Speed / Time / Distance Calculator

Solve cycling speed, time or distance. Uses transparent local arithmetic and independent verification.

Open tool Health, Fitness & Sports

Cycling Power-to-Weight Calculator

Calculate watts per kilogram and scenario changes. Uses local formulas and independent verification.

Open tool Health, Fitness & Sports

Bicycle Gear Calculator

Calculate gear inches, development and speed from chainring, sprocket, wheel and cadence. Uses local formulas and independent verification.

Open tool Health, Fitness & Sports

Swimming Pace Calculator

Convert time, distance and pace per 25, 50 or 100 units. Uses transparent local arithmetic and independent verification.

Open tool Health, Fitness & Sports

Rowing Pace Calculator

Convert 500 m split, watts, time and distance using ergometer formulas. Uses local formulas and independent verification.

Open tool Health, Fitness & Sports

One Rep Max Calculator

Estimate 1RM from weight and repetitions using multiple formulas. Uses transparent local arithmetic and independent verification.

Open tool Health, Fitness & Sports

Barbell Plate Calculator

Calculate plates per side from target weight, bar and available plates. Uses transparent local arithmetic and independent verification.

Open tool Health, Fitness & Sports

Boxing Round Timer

Run configurable boxing or kickboxing rounds, warnings and rest periods. Uses transparent local arithmetic and independent verification.

Open tool Health, Fitness & Sports

BJJ Round Timer

Run configurable grappling rounds, rest periods and round counts. Uses transparent local arithmetic and independent verification.

Open tool Health, Fitness & Sports

Steps to Distance Calculator

Estimate distance from step count and user-entered or estimated stride length. Uses local formulas and independent verification.

Open tool Health, Fitness & Sports

Distance to Steps Calculator

Estimate steps from distance and stride length. Uses local formulas and independent verification.

Open tool Science & Engineering

Ohm's Law Calculator

Solve voltage, current, resistance and power from any two compatible values. Uses explicit SI units, local arithmetic and independent verification.

Open tool Science & Engineering

Electrical Power Calculator

Calculate DC or single-phase power, voltage, current, resistance and energy. Uses explicit SI units, local arithmetic and independent verification.

Open tool Science & Engineering

Resistors in Series Calculator

Calculate total resistance, voltage drops and power from entered resistors. Uses explicit SI units, local arithmetic and independent verification.

Open tool Science & Engineering

Resistors in Parallel Calculator

Calculate equivalent resistance and branch currents. Uses explicit SI units, local arithmetic and independent verification.

Open tool Science & Engineering

Resistor Color Code Calculator

Decode and generate 3–6 band resistor color codes. Uses explicit SI units, local arithmetic and independent verification.

Open tool Science & Engineering

SMD Resistor Code Calculator

Decode common numeric and EIA-96 SMD resistor markings. Uses explicit SI units, local arithmetic and independent verification.

Open tool Science & Engineering

LED Resistor Calculator

Calculate series resistor and power rating from supply, forward voltage and current. Uses explicit SI units, local arithmetic and independent verification.

Open tool Science & Engineering

Voltage Divider Calculator

Solve output voltage or resistor values and show loading assumptions. Uses explicit SI units, local arithmetic and independent verification.

Open tool Science & Engineering

Capacitor Combination Calculator

Calculate equivalent capacitance in series or parallel. Uses explicit SI units, local arithmetic and independent verification.

Open tool Science & Engineering

RC Time Constant Calculator

Calculate time constant and charge/discharge milestones. Uses explicit SI units, local arithmetic and independent verification.

Open tool Science & Engineering

Force Calculator

Calculate force, mass or acceleration from Newton's second law. Uses local SI formulas and independent verification.

Open tool Science & Engineering

Work Calculator

Calculate mechanical work from force, displacement and angle. Uses local SI formulas and independent verification.

Open tool Science & Engineering

Power / Work / Time Calculator

Solve mechanical power, work or time. Uses local SI formulas and independent verification.

Open tool Science & Engineering

Kinetic Energy Calculator

Calculate kinetic energy, mass or velocity. Uses local SI formulas and independent verification.

Open tool Science & Engineering

Gravitational Potential Energy Calculator

Calculate energy, mass, gravity or height. Uses local SI formulas and independent verification.

Open tool Science & Engineering

Momentum Calculator

Calculate linear momentum from mass and velocity. Uses local SI formulas and independent verification.

Open tool Science & Engineering

Projectile Motion Calculator

Calculate trajectory values for an ideal projectile with selectable gravity. Uses local SI formulas and independent verification.

Open tool Science & Engineering

Free Fall Calculator

Calculate distance, time and velocity under constant gravity. Uses local SI formulas and independent verification.

Open tool Science & Engineering

Centripetal Force Calculator

Calculate centripetal force, mass, speed or radius. Uses local SI formulas and independent verification.

Open tool Science & Engineering

Torque Calculator

Calculate torque from force, lever arm and angle. Uses local SI formulas and independent verification.

Open tool Science & Engineering

Mechanical Advantage Calculator

Calculate ideal mechanical advantage for levers, pulleys, wheels and inclined planes. Uses local SI formulas and independent verification.

Open tool Science & Engineering

Hooke's Law Calculator

Calculate force, displacement or spring constant. Uses local SI formulas and independent verification.

Open tool Travel, Maps & Coordinates

Great-circle Distance Calculator

Calculate shortest surface distance between coordinates using a selected Earth model. Uses explicit geospatial assumptions and independent local verification.

Open tool Travel, Maps & Coordinates

Initial Bearing Calculator

Calculate initial and final bearings between two coordinates. Uses explicit geospatial assumptions and independent local verification.

Open tool Travel, Maps & Coordinates

UTM Coordinate Converter

Convert supported WGS84 latitude/longitude and UTM coordinates locally. Uses explicit geospatial assumptions and independent local verification.

Open tool Travel, Maps & Coordinates

Geohash Encoder / Decoder

Encode coordinates to geohash and decode cells, center and bounds. Uses explicit geospatial assumptions and independent local verification.

Open tool Travel, Maps & Coordinates

GeoJSON Viewer

Validate and render supplied GeoJSON locally on an offline-capable map canvas. Uses explicit geospatial assumptions and independent local verification.

Open tool Travel, Maps & Coordinates

GeoJSON Formatter & Validator

Format and validate geometry types, coordinates and properties. Uses explicit geospatial assumptions and independent local verification.

Open tool Randomizers, Decisions & Everyday

Wheel Spinner

Spin a customizable wheel uing cryptographic or seeded randomness and save local presets. Keeps list data local and exposes randomness and duplicate rules.

Open tool Randomizers, Decisions & Everyday

Random Name Picker

Choose one or more names from a pasted list with optional removal after selection. Keeps list data local and exposes randomness and duplicate rules.

Open tool Randomizers, Decisions & Everyday

Random Team Generator

Split a list into balanced random teams with exclusions and seeded results. Keeps list data local and exposes randomness and duplicate rules.

Open tool Randomizers, Decisions & Everyday

Random Pair Generator

Create random pairs or small groups and handle an odd participant. Keeps list data local and exposes randomness and duplicate rules.

Open tool Randomizers, Decisions & Everyday

Random Order Generator

Shuffle a list and export numbered order with a reproducible seed. Keeps list data local and exposes randomness and duplicate rules.

Open tool Randomizers, Decisions & Everyday

Raffle Winner Picker

Select auditable winners from an imported list without contacting a social platform. Keeps list data local and exposes randomness and duplicate rules.

Open tool Randomizers, Decisions & Everyday

Coin Flip

Flip one or many virtual coins using cryptographic randomness. Uses explicit bounds and independent local verification.

Open tool Randomizers, Decisions & Everyday

Random String Generator

Generate strings from selected character sets with cryptographic randomness. Uses explicit bounds and independent local verification.

Open tool Career, Work & Project Management

Resume Builder

Build a clean resume locally and export HTML or print-ready PDF. Uses editable assumptions, local execution and independent artifact verification.

Open tool Career, Work & Project Management

ATS Resume Checker

Check your résumé's structure, headings, tables, contact fields and parseability locally, without claiming compatibility with any employer's ATS.

Open tool Career, Work & Project Management

Resume vs Job Description Matcher

Compare user-provided documents for exact and related keyword coverage locally. Uses editable assumptions, local execution and independent artifact.

Open tool Career, Work & Project Management

Salary Offer Comparison Calculator

Compare salary, bonus, benefits, commute and work-hours assumptions across offers. Uses editable assumptions, local execution and independent artifact.

Open tool Career, Work & Project Management

Meeting Cost Calculator

Estimate meeting cost from duration, attendees and loaded hourly rates. Uses editable assumptions, local execution and independent artifact verification.

Open tool Career, Work & Project Management