💻 Developer Tools
Format, encode, decode and inspect data in one click
Every developer needs a reliable toolbox: format a minified JSON response, decode a Base64 payload, convert a Unix timestamp into a readable date, encode a URL parameter or inspect the claims inside a JWT. These tools do the small jobs that would otherwise mean digging through language docs or installing packages.
ToolNest's developer tools are built with the same standard libraries you use in production — JSON.parse, Web Crypto, TextEncoder — so results match what your code will do. Everything runs client-side, which also makes these tools safe for inspecting tokens and payloads that contain sensitive data: nothing ever leaves your machine.
JSON Formatter
Beautify, validate and minify JSON data.
🔥Base64 Encoder / Decoder
Convert text to and from Base64, UTF-8 safe.
Unix Timestamp Converter
Epoch seconds and milliseconds to dates — and back.
🔥URL Encoder / Decoder
Encode and decode URLs and query parameters safely.
🔥UUID Generator
Generate cryptographically random UUIDs (v4) in bulk.
HTML Entity Converter
Escape and unescape HTML entities safely.
JWT Decoder
Inspect JWT header and payload claims — offline and private.
XML Formatter
Format, indent and validate XML documents.
CSS Minifier / Beautifier
Minify CSS for production or beautify it for reading.
Cron Expression Explainer
Translate cryptic cron expressions into plain English.
Need a tool we don't have yet?
Requests with 3 votes go straight into our build queue — visit the homepage search to request one.