Free Developer Tools
Free developer tools that run entirely in your browser — JSON formatter, Base64, hashing, JWT, regex, UUID, and more. No data leaves your device.
JSON Formatter & Validator
Format, beautify, minify, and validate JSON with clear error messages.
Base64 Encode / Decode
Encode text to Base64 or decode Base64 back to text, with full Unicode support.
URL Encode / Decode
Percent-encode or decode text for safe use in URLs and query strings.
Hash Generator
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from any text.
JWT Decoder
Decode a JSON Web Token to read its header and payload claims.
UUID Generator
Generate one or many random version-4 UUIDs instantly.
Unix Timestamp Converter
Convert between Unix timestamps and human-readable dates, both ways.
Regex Tester
Test regular expressions live with match highlighting and capture groups.
Color Converter
Convert colors between HEX, RGB, and HSL with a live swatch preview.
Text Diff Checker
Compare two blocks of text and highlight every added, removed, and unchanged line.
Number Base Converter
Convert numbers between binary, octal, decimal, and hexadecimal instantly.
JSON ↔ CSV Converter
Convert a JSON array of objects to CSV and back, right in your browser.
HTML Entity Encoder / Decoder
Encode special characters to HTML entities or decode entities back to text.
Markdown Previewer
Write Markdown and see a live HTML preview, then copy the generated HTML.
JSON ↔ YAML Converter
Convert JSON to YAML and YAML to JSON instantly, with validation, in your browser.
CSS Gradient Generator
Build linear and radial CSS gradients visually with live preview and copyable CSS code.
Color Palette Generator
Generate harmonious color palettes and shade scales from a base color, with hex codes to copy.
Favicon Generator
Turn any image into favicon sizes (16–512px) and download them all as a ZIP, in your browser.
Cron Expression Parser
Translate a cron expression into plain English and see the next scheduled run times.
Code Beautifier & Minifier
Beautify or minify HTML, CSS, and JavaScript instantly, right in your browser.
SQL Formatter
Format and beautify SQL queries with indentation and keyword casing, for many SQL dialects.
JSON ↔ XML Converter
Convert JSON to XML and XML to JSON, with formatting, in your browser.
Image to Base64 Converter
Encode an image to a Base64 data URI (and back), with ready-to-paste HTML and CSS snippets.
JSON to TypeScript
Generate TypeScript interfaces from any JSON object, with nested types inferred automatically.
IP Subnet Calculator
Compute network, broadcast, host range, and mask from an IPv4 address and CIDR or subnet mask.
Meta Tag Generator
Generate SEO and Open Graph meta tags for your web page from a simple form.
HMAC Generator
Generate an HMAC signature from a message and secret key using SHA-256, SHA-384, or SHA-512.