Free online tools that run in your browser
BrowserTools is a growing collection of 100 focused utilities, converters, validators, encoders, calculators, networking helpers and a few classic games. Each one does a single job well, with no signup and no clutter.
Whenever a task can run on your own machine, it does: the file you paste, drop or type never leaves your browser, and there is nothing to install. The handful of tools that genuinely need a server (DNS, ping, WHOIS) call a small backend that does only what you ask and stores nothing about you.
- 100 tools
- 100% in your browser
- No signup
- No tracking
- Free & open in spirit
Audio 4
Audio Compressor
Shrink audio files by re-encoding to a smaller MP3 bitrate, locally in your browser.
Audio Converter
Convert audio between MP3, WAV, OGG/Opus, M4A/AAC and FLAC locally in your browser.
Audio Joiner (Merge Audio)
Merge several audio files into one track locally in your browser, in any order.
Audio Trimmer & Cutter
Trim or cut a section from an audio file locally in your browser, fast and without re-encoding.
Calculators 8
Aspect Ratio Calculator
Keep images and videos in proportion. Enter a ratio and one dimension to compute the other instantly.
BMI Calculator
Calculate your Body Mass Index in metric or imperial units and see your weight category instantly.
Compound Interest & Savings Calculator
Project the growth of your savings with monthly contributions, compound frequency and inflation-adjusted results.
Date Calculator
Calculate age from a date of birth, find the interval between two dates, or add and subtract time from any date.
Loan Comparison Calculator
Compare up to three loans side-by-side: monthly payment, total interest and total cost.
Mortgage & Loan Calculator
Calculate monthly mortgage or loan payments and visualize the full amortization schedule.
Percentage Calculator
Calculate percentages every way: X% of Y, what % is X of Y, percent change, increase or decrease.
Tip Calculator & Bill Splitter
Compute tip amount and split a bill evenly between any number of people.
Converters 12
Bytes Converter (KB, MB, GB, TB)
Convert between bytes, KB/MB/GB/TB and KiB/MiB/GiB/TiB, both decimal (base 10) and binary (base 2).
Color Converter & Contrast Checker
Convert colors between HEX, RGB, HSL and HSV, plus WCAG contrast ratio checker.
CSV ↔ JSON Converter
Convert between CSV and JSON locally with custom delimiters and quoting, no upload, no limits.
EV Efficiency Converter (Wh/km, kWh/100km, mi/kWh, MPGe)
Convert electric vehicle efficiency between Wh/km, kWh/100km, mi/kWh and MPGe. Estimate range and charging cost.
Fuel Consumption Converter (L/100km, MPG, km/L)
Convert vehicle fuel economy between L/100km, US MPG, UK MPG and km/L, and estimate trip cost.
JSON to YAML Converter
Convert between JSON and YAML both ways, privately in your browser.
Number Base Converter (Binary, Octal, Decimal, Hex)
Convert numbers between binary, octal, decimal, hexadecimal and any custom base from 2 to 36.
Roman Numerals Converter
Convert between Arabic numbers and Roman numerals (1 to 3,999,999) with a vinculum-aware algorithm.
Temperature Converter (°C, °F, K)
Convert temperatures between Celsius, Fahrenheit, Kelvin and Rankine instantly.
Text Case Converter
Convert text to UPPERCASE, lowercase, Title Case, camelCase, snake_case, kebab-case, a URL slug and more, instantly in your browser.
Unix Timestamp Converter
Convert between Unix timestamps and human-readable dates in any timezone, with millisecond precision.
Unit Converter
Convert between common units of length, mass, temperature, time and digital storage.
Encoders 9
Base64 Encoder & Decoder
Encode and decode Base64 text or files locally in your browser.
Basic Auth Header Generator
Build and decode HTTP Basic authentication headers from a username and password, entirely in your browser.
Bcrypt Generator & Verifier
Generate bcrypt password hashes and verify a password against an existing hash, entirely in your browser.
Escape & Unescape Tool
Escape or unescape text for HTML, XML, JSON, JavaScript, CSV and URLs, locally in your browser.
Hash Generator (SHA-1, SHA-256, SHA-384, SHA-512)
Compute cryptographic hashes of text or files locally, SHA-1, SHA-256, SHA-384 and SHA-512.
JWT Decoder
Decode and inspect JSON Web Tokens locally, header, payload and expiry claims.
JWT Generator (HS256)
Create signed HS256 JSON Web Tokens locally in your browser, nothing uploaded.
Text Encrypt / Decrypt (AES-GCM)
Encrypt and decrypt text with a password using AES-GCM, all locally in your browser.
URL Encode / Decode
Percent-encode or decode URLs and query parameters, component-safe and full-URI modes.
Entertainment 9
2048, Sliding Tile Puzzle
Play 2048 in your browser. Slide tiles on a 4×4 grid, merge equal numbers, and reach the 2048 tile.
Breakout, Classic Brick Breaker
Play classic Breakout in your browser. Bounce the ball, smash bricks, and clear all levels.
Retro Game Emulator, Play ROMs in Browser
Play classic retro console games in your browser. Load a ROM file and start playing, NES, SNES, GBA, N64, Sega, and more.
Minesweeper, Classic Browser Game
Play the classic Minesweeper game in your browser. Three difficulty levels, flag mines, beat your best time.
Snake, Classic Browser Game
Play the classic Snake game in your browser. Eat food, grow longer, and avoid hitting walls or yourself.
Klondike Solitaire, Classic Card Game
Play classic Klondike Solitaire in your browser. Draw 1 or Draw 3, auto-move to foundations, no installation needed.
Sudoku, Classic Number Puzzle
Play Sudoku in your browser. Three difficulty levels, mistake tracking, timer, and a built-in solver.
Tetris, Classic Falling Blocks
Play classic Tetris in your browser. Rotate and place falling tetrominoes, clear lines, and beat your high score.
Typing Speed Test, WPM Tester
Test your typing speed online. Get your WPM and accuracy in 15, 30, or 60 seconds. No sign-up required.
Generators 11
Barcode Generator
Create CODE128, EAN13, UPC and CODE39 barcodes in your browser and download them as PNG or SVG.
CSS Box Shadow Generator
Design CSS box shadows visually with live preview and copy-ready code, all in your browser.
Color Palette Generator
Generate complementary, analogous, triadic, tetradic, monochromatic and shade/tint palettes from any base color.
Cron Expression Generator & Explainer
Build and decode cron schedules into plain English, entirely in your browser.
Cubic Bezier Easing Generator
Design CSS cubic-bezier easing curves with two draggable control points, presets, a live animation preview and copy-ready code, all in your browser.
CSS Gradient Generator
Build linear, radial and conic CSS gradients with a live preview and copy-ready code.
Lorem Ipsum Generator
Generate placeholder Lorem Ipsum text, paragraphs, sentences, words or HTML lists.
Password & Passphrase Generator
Generate strong random passwords and memorable passphrases locally, fully customizable.
QR Code Generator
Generate QR codes for URLs, text, Wi-Fi credentials and contact cards. Download as PNG or SVG.
QR Code Scanner
Scan QR codes from your camera or an uploaded image, entirely in your browser.
UUID Generator (v1, v4, v7)
Generate RFC 4122 UUIDs in version 1, 4 or 7, single or in bulk, copy or download.
Images 7
EXIF Viewer & Remover
View the EXIF metadata hidden in a photo, including camera and GPS data, then download a clean copy with the metadata stripped, all in your browser.
Favicon Generator
Generate favicon PNGs at every standard size and a multi-resolution .ico file from any image, entirely in your browser.
Image Converter (PNG / JPG / WEBP)
Convert and resize images locally in your browser using the Canvas API. No uploads.
Image Compressor (JPG / WEBP / PNG)
Reduce image file size with adjustable quality, see before/after side by side.
Image Cropper
Crop images to any region or fixed aspect ratio and export as PNG or JPEG, entirely in your browser.
Image Resizer, Resize Photos Online
Resize images by width, height or percentage, lock the aspect ratio and pick a fit mode. 100% in your browser, no uploads.
SVG Optimizer
Clean and shrink SVG files by removing editor metadata, comments and redundant whitespace, locally in your browser.
Misc 5
Countdown Timer
Count down to any date and time with a live display of days, hours, minutes and seconds.
Diff Checker (Text Compare)
Compare two blocks of text line by line and see exactly what was added, removed or kept, entirely in your browser.
Random Picker, List, Coin, Dice, Number
Pick a random item from a list, flip a coin, roll dice, or generate a random number.
Stopwatch & Timer
Online stopwatch with lap times and a countdown timer with audible alarm, all in your browser.
Word & Character Counter
Count words, characters, sentences, paragraphs and reading time as you type, entirely in your browser.
Networking 8
DNS Lookup
Query DNS records (A, AAAA, MX, TXT, NS, CNAME, SOA, CAA) for any public domain.
IP Subnet Calculator (CIDR / IPv4)
Calculate network address, broadcast, mask, host range and total hosts from any IPv4 CIDR notation.
IPv6 Expander & Compressor
Expand any IPv6 address to its full 8-group form or compress it to the RFC 5952 canonical form, locally in your browser.
What's My IP, User Agent & Browser Info
See your public IP address, user agent, request headers and browser capabilities, instant lookup, no tracking.
TCP Port Check (Ping)
Check if a TCP port on a public host is open and measure connection latency.
URL Parser
Break any URL into its scheme, host, port, path, query parameters and hash, parsed locally in your browser.
User-Agent Parser
Parse a User-Agent string into browser, engine, OS and device information.
WHOIS Lookup
Look up the WHOIS registration data for any public domain, registrar, dates and nameservers.
PDF 11
Images to PDF
Combine PNG, JPG and WEBP images into a single PDF document, in your browser, no uploads.
Markdown to PDF Converter
Convert Markdown to a clean, printable PDF locally in your browser, with live preview and no uploads.
PDF Compress (Optimize Size)
Reduce the size of a PDF locally by re-saving it with object streams and stripping unused metadata.
Delete Pages from PDF
Remove specific pages from a PDF using a simple range like 2,5-7 and download the trimmed file, locally in your browser.
Extract Text from PDF
Pull all selectable text out of a PDF into plain text you can copy or download, locally in your browser.
PDF Merge, Combine PDFs Online
Merge multiple PDF files into one document, fully in your browser. Drag to reorder, no uploads.
Add Page Numbers to PDF
Stamp page numbers like 3 / 12 onto every page of a PDF, with a choice of corner positions, locally in your browser.
Rotate PDF Pages
Rotate all or specific pages of a PDF by 90°, 180° or 270°, locally in your browser.
PDF Split, Extract or Separate Pages
Split a PDF into single pages or extract a custom page range, entirely in your browser, no uploads.
PDF to Images (PNG / JPG)
Convert each page of a PDF to PNG or JPG images, entirely in your browser.
Add Watermark to PDF
Stamp a diagonal text watermark like CONFIDENTIAL across every page of a PDF, locally in your browser.
Validators 6
HTML / CSS / JS Beautifier & Minifier
Beautify or minify HTML, CSS, and JavaScript locally in your browser.
JSON Validator & Formatter
Validate, format and minify JSON in your browser with detailed error locations.
Password Strength Checker
Test how strong a password is: entropy, estimated crack time and a clear checklist, all checked locally in your browser.
Regex Tester & Debugger
Test JavaScript regular expressions live with match highlighting, capture groups and replace preview.
SQL Formatter & Minifier
Pretty-print or minify SQL for several dialects, all locally in your browser.
XML Validator & Formatter
Validate and pretty-print XML in your browser using the DOMParser.
Video 10
GIF to Video (MP4/WebM)
Convert an animated GIF to a much smaller MP4 or WebM video locally in your browser.
Extract Audio from Video
Pull the audio track out of a video and save it as MP3, M4A, WAV or Opus, locally in your browser.
Video Compressor
Compress and shrink video files locally in your browser, no upload, no quality wall.
Video Converter
Convert video between MP4, WebM, MOV, MKV, AVI and GIF locally in your browser.
Mute Video (Remove Audio)
Remove the audio track from a video locally in your browser, fast and without re-encoding the picture.
Video Resizer (Change Resolution)
Scale a video down to 1080p, 720p, 480p and more locally in your browser, keeping the aspect ratio.
Rotate & Flip Video
Rotate a video 90° or 180°, or flip it horizontally or vertically, locally in your browser.
Change Video Speed
Speed up or slow down a video (with pitch-corrected audio) locally in your browser.
Video to GIF Converter
Turn a video or clip into an animated GIF locally in your browser, with adjustable size and frame rate.
Video Trimmer & Cutter
Trim or cut a clip from a video locally in your browser, fast and without re-encoding.
How these tools work
Most utilities here are client-side: the logic ships as a small JavaScript module that runs in your browser, so your text and files are processed locally and never uploaded. That keeps things fast, works offline once the page has loaded, and means a sensitive document (a PDF you need to split, an image you want to resize) stays on your device.
Every tool page includes a short explanation of what the tool does, worked context, and answers to common questions, so you can understand the format or technique, not just click a button. If a tool can ever give a wrong or surprising result for a particular input, we try to say so on the page.
Have an idea for a tool, spotted a bug, or got a result that looks off? Tell us on the contact page, feedback is how the catalogue improves. You can also read about who runs BrowserTools and our privacy approach.