Developer Tools Tools

Formatters, validators, encoders, decoders and generators for programmers.

• JSON Formatter — Beautify or minify JSON with 2-space, 4-space or tab indents, sort keys and browse it as a collapsible tree.
• JSON Validator — Check JSON syntax as you type, see the exact line and column of any error and get warnings for duplicate keys.
• XML Formatter — Pretty-print or minify XML with comments, CDATA and DOCTYPE support, plus a well-formedness check with error positions.
• HTML Formatter — Beautify HTML with your choice of indentation and line wrapping, including inline <script> and <style> blocks.
• CSS Formatter — Beautify minified CSS into readable rules with custom indentation, brace style and one selector per line.
• JavaScript Formatter — Beautify JavaScript with configurable indentation, brace style and line wrapping to make minified code readable.
• Code Minifier — Minify JavaScript with Terser, plus CSS and HTML, and see the original size, minified size and percentage saved.
• Base64 Encoder — Encode text or files up to 10 MB to Base64, Base64URL or a data URL, with full UTF-8 support for any language.
• Base64 Decoder — Decode Base64, Base64URL or data URLs to text, detect invalid characters and download decoded binary files.
• JWT Decoder — Decode a JSON Web Token header and payload, see iat, nbf and exp as dates, and optionally verify HS256 signatures.
• UUID Generator — Generate up to 1,000 random v4 or time-ordered v7 UUIDs at once, and validate any UUID to see its version.
• Regex Tester — Test JavaScript regular expressions with live match highlighting, capture groups, named groups and a replace preview.
• Markdown Previewer — Write GitHub-flavoured Markdown with a live, sanitised preview, then copy the HTML or download .md and .html files.