Free Online Tools for Developers
Format, convert, encode and generate — 46 fast, privacy-friendly tools that run entirely in your browser. No sign-up, no uploads, no limits.
Private by design
Every tool runs locally in your browser. Your data is never uploaded, logged or stored on a server.
Instant results
No round-trips to a backend. Formatting and conversion happen as fast as you can click.
Free, supported by ads
All tools are free to use. The site is funded by unobtrusive advertising — you can decline optional cookies.
🛠️ Formatters
Clean up messy code and spot syntax errors in seconds.
JSON Formatter & Validator
Beautify, minify and validate JSON with clear error locations.
XML Formatter
Pretty-print, minify and check that XML is well-formed.
HTML Formatter
Indent messy HTML or minify it for production.
CSS Formatter
Beautify stylesheets or strip them down with one click.
SQL Formatter
Re-indent SQL queries and normalise keyword casing.
JavaScript Formatter
Re-indent and space-out minified or messy JavaScript.
Java Formatter
Re-indent Java source with braces, generics and comments handled.
🗜️ Minifiers
Shrink code and payloads — safe, validated, one click.
JSON Minifier
Compress JSON to a single line, validated as it shrinks.
XML Minifier
Strip insignificant whitespace from XML documents.
HTML Minifier
Shrink HTML pages by collapsing whitespace.
CSS Minifier
Minify stylesheets: remove comments and extra whitespace.
SQL Minifier
Collapse SQL to one line while preserving strings and comments.
JavaScript Minifier
Safely strip comments and indentation from JavaScript.
🔄 Converters
Move your data between the formats you need.
CSV to JSON Converter
Turn delimited data into a JSON array of objects.
JSON to CSV Converter
Flatten a JSON array into CSV for spreadsheets.
JSON to XML Converter
Transform JSON objects and arrays into XML elements.
XML to JSON Converter
Convert XML documents to JSON, attributes included.
Unix Timestamp Converter
Convert epoch timestamps to dates and back, both directions.
Number Base Converter
Binary, octal, decimal, hex and base-36 — any direction.
Text to Binary Converter
Encode text as UTF-8 binary or turn binary back into text.
Text to Hex Converter
Convert text to hexadecimal bytes and back, with separators.
Color Converter
HEX, RGB and HSL at a glance, with a live preview swatch.
Unit Converter
Length, weight, temperature, speed, area and data sizes.
Markdown to HTML Converter
Turn Markdown headings, lists and links into clean HTML.
🔐 Encoders & Escapers
Safely encode, escape and decode text for any context.
Base64 Encoder & Decoder
Encode text to Base64 or decode it, with full UTF-8 support.
URL Encoder & Decoder
Percent-encode URLs and query strings or decode them.
HTML Escape / Unescape
Escape text for safe HTML output, or decode entities.
JSON Escape / Unescape
Escape any text as a JSON string literal and back.
XML Escape / Unescape
Escape text for XML documents and attributes, and back.
Java String Escape / Unescape
Escape text for Java string literals — \n, \t, \uXXXX and friends.
Image to Base64
Turn an image into a Data URI, or preview Base64 back as an image.
JWT Decoder
Inspect JWT headers and payloads — fully offline, nothing stored.
ROT13 / Caesar Cipher
Shift letters by 13 (ROT13) or any amount, in both directions.
🔍 Validators & Testers
Check patterns and schedules before they hit production.
✨ Generators
Create test data, identifiers and strong credentials.
UUID Generator
Create random UUID v4 identifiers in bulk, online and offline.
Password Generator
Strong random passwords, generated on your device.
Lorem Ipsum Generator
Placeholder paragraphs, sentences or words for mock-ups.
Random Number Generator
Cryptographically secure numbers in any range, with options.
Test Data Generator
Fake names, emails, addresses and more for your test databases.
🧰 Utilities
Small helpers you'll reach for every day.
Hash Generator
MD5, SHA-1, SHA-256, SHA-384 and SHA-512 in one place.
Word & Character Counter
Live word, character, sentence and paragraph statistics.
Text Case Converter
UPPERCASE, camelCase, snake_case and eight more styles.
Slug Generator
Turn any title into a clean, URL-safe slug.
Text Cleaner
Dedupe, sort, trim, join and clean up lines in one place.
Text Diff Checker
Compare two texts and see added and removed lines, highlighted.