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1119+ tools for developers, designers, and everyday tasks. Most tools run in your browser — your data stays on your device. Some tools require external services.
Top 20 Popular Tools
View all →JSON Formatter
Format, beautify and validate JSON instantly in your browser. No upload, fully private.
Base64 Encoder
Encode text to Base64 instantly in your browser. No upload, no signup, fully private.
Base64 Decoder
Decode Base64 to text instantly in your browser. Supports UTF-8. No upload, fully private.
URL Encoder
Encode text to URL-safe format (percent-encoding) instantly in your browser. No upload, fully private.
URL Decoder
Decode URL-encoded text (percent-encoding) back to original instantly in your browser. No upload, fully private.
UUID Generator
Generate random UUIDs (v4) instantly in your browser. No upload, fully private.
Password Generator
Generate strong, random passwords with customizable length and character sets. Uses crypto.getRandomValues.
Free QR Code Generator
Free online free qr code generator. Process data instantly in your browser. No upload, no signup, fully private.
Color Picker
Pick colors and get HEX, RGB, and HSL values in your browser. Free, online, no upload, fully private.
Image Compressor
Compress images in your browser to reduce file size. Adjust quality and download the optimized image. Free, private, no upload.
Image Resizer
Resize images in your browser. Set custom dimensions or maintain aspect ratio. Download the resized image.
PDF Merger
PDF manipulation tool. Coming soon.
PDF to Text Converter
Extract text content from PDF files in your browser. Free, online, no upload, fully private.
Hash Generator
Generate SHA-256, SHA-1, SHA-512 and SHA-384 hashes from any text. Uses Web Crypto API, fully private.
JWT Decoder
Decode JWT tokens and inspect the header and payload. See the decoded JSON content instantly.
Regex Tester
Test regular expressions against any text in real-time. See all matches instantly with match count.
Timestamp Converter
Convert Unix timestamps to human-readable dates and vice versa. Supports ISO 8601 format.
Word Counter
Count words, characters, sentences and paragraphs in your text instantly. No upload, fully private.
Markdown Preview
Write markdown and see a live preview instantly. Supports headings, bold, italic, links, lists and more.
CSS Unit Converter
Convert CSS units between px, rem, em, pt, mm, cm, and inches. Essential for responsive design.
Browse by Function
Developer & Code
Text & Content
Design & Media
Color Tools
HEX, RGB, HSL, CMYK conversion, color picker, palette generator and contrast checker.
Image Tools
Resize, compress, convert, crop, rotate and edit images entirely in your browser. No upload required.
PDF Tools
Merge, split, compress, convert and manipulate PDF files locally. Your PDFs never leave your device.
QR & Barcode Tools
Generate and decode QR codes, barcodes and other 2D codes locally.
Audio Tools
Audio converter, volume normalizer, waveform viewer and audio utilities.
Video Tools
Video converter, trimmer, metadata viewer and video utilities.
Network & Security
Calculators & Math
Date & Time
Finance & Business
Health & Life
Productivity & Fun
Productivity Tools
Pomodoro timer, task list, note pad and workflow helpers.
Social Media Tools
Character counter for posts, image resizer for platforms, hashtag generator.
AI Utilities
Token counter, prompt template, JSONL formatter and AI workflow helpers.
Random & Fun Tools
Dice roller, coin flip, random picker, trivia and entertainment tools.
File Tools
File hash, rename, format detection, metadata viewer and general file utilities.
Guides & Tutorials
How to Encode and Decode Base64: A Complete Guide
Learn what Base64 encoding is, how it works, when to use it, and how to encode and decode Base64 in your browser —no tools or signup needed.
explanationColor Formats Explained: HEX, RGB, and HSL
Understand the three most common web color formats —HEX, RGB, and HSL —how each represents color, when to use which, and how to convert between them.
referenceDNS Records Explained: A, AAAA, MX, TXT, CNAME, NS
A complete reference guide to DNS record types —A, AAAA, MX, TXT, CNAME, and NS —with examples, use cases, and how to look them up.
explanationHashing Algorithms Explained: MD5, SHA-1, SHA-256, SHA-512
Understand how cryptographic hash functions work, the differences between MD5, SHA-1, SHA-256, and SHA-512, and which to use for integrity checks vs password storage.
explanationJSON Formatting Best Practices: Readable, Valid, and Efficient
Understand the conventions for formatting JSON: indentation, key ordering, minification, trailing commas, and when to pretty-print vs minify.
explanationUnderstanding JSON: A Beginner's Guide to Formatting and Validation
Learn what JSON is, its syntax rules, common data types, and how to format and validate JSON data using free online tools.
how-toHow to Decode a JWT and Inspect Its Claims Safely
Learn the three-part structure of a JSON Web Token, how to decode the header and payload without verifying, and why decoding is not the same as trusting.
comparisonMarkdown vs HTML: Which Should You Use for Content?
Compare Markdown and HTML across readability, expressiveness, learning curve, use cases, and rendering —and learn when to pick each (or both).
problem-solvingPassword Security: How to Generate, Store, and Audit Strong Passwords
Solve the most common password security problems: generating strong passwords, hashing them correctly, avoiding reuse, and auditing existing credentials.
referenceRegular Expressions Cheat Sheet: Syntax, Flags, and Common Patterns
A complete reference for regular expression syntax: metacharacters, character classes, quantifiers, anchors, groups, flags, and ready-to-use patterns for emails, URLs, dates, and more.
how-toHow to Convert Unix Timestamps to Human-Readable Dates
Learn what a Unix timestamp is, how to convert it to a human-readable date and back, and how to handle time zones correctly when working with epoch time.
referenceUnit Conversion Reference: Length, Mass, Temperature, and Area
A complete reference of conversion factors for length, mass/weight, temperature, and area, with exact formulas and worked examples for each.
how-toHow to Encode and Decode URLs: A Complete Guide
Learn what URL encoding (percent-encoding) is, why it is required, and how to encode and decode URLs in your browser —no signup, fully private.
comparisonUUID v1 vs v4 vs v5: Which Version Should You Use?
Compare UUID versions 1, 4, and 5: how each is generated, their trade-offs in uniqueness, ordering, and determinism, and which to pick for your use case.
how-toHow to Count Words, Characters, and Reading Time Accurately
Learn how word and character counts are defined across languages, how to estimate reading time, and how to use a counter to hit limits for essays, tweets, and meta descriptions.
Reference Library
Base64 Character Table Reference
Complete Base64 encoding character table with all 64 characters, their indices, binary values, and ASCII codes.
ISO 3166-1 Country Codes Reference
ISO 3166-1 country codes including alpha-2, alpha-3, and numeric codes for 55+ common countries.
CSS Named Colors Reference
All CSS named colors with hex and RGB values.
ISO 4217 Currency Codes Reference
ISO 4217 currency codes with names, symbols, and issuing countries for 40+ common currencies.
File Extensions Reference
Common file extensions with MIME types, categories, and descriptions for quick lookup.
HTML Entities Reference
Common HTML character entities with names, decimal and hex codes.
HTTP Status Codes Reference
Complete reference of HTTP status codes with descriptions, categories, and usage examples.
JSON Syntax Reference
Complete JSON (RFC 8259) syntax reference with data types, grammar rules, examples, and common errors.
MIME Types Reference
Common MIME types (Internet media types) with file extensions and descriptions.
Regular Expressions Cheat Sheet
Quick reference for regular expression syntax including characters, quantifiers, anchors, groups, and common patterns.
IANA Time Zones Reference
IANA time zone identifiers with UTC offsets and descriptions for 40 common time zones worldwide.
Unix Timestamp Reference
Unix timestamp reference with common milestones, value ranges, and conversion rules.
Why FreeOnlineTools?
100% Free
All tools are free. No signup, no subscription, no hidden costs.
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Most tools process data locally in your browser. For those tools, your files never leave your device.
Fast & Browser-Based
No downloads or installs. Most tools run instantly in your browser with Web APIs.
Growing Library
We're building 200+ tools to cover all your daily needs. New tools added regularly.