JSON, regex, JWT and 32 more developer tools · Free developer tools app for your browser
Thirty-five developer tools in one fast app, all running in your browser so nothing you paste is ever uploaded. Format and validate JSON with the exact line of any mistake, a tree view and JSONPath; test a regular expression with every match highlighted and the pattern explained in plain English; decode a JWT and verify its signature; encode and decode Base64 and URLs; get MD5 and SHA hashes of text or files; generate UUID v4 and v7, ULIDs and NanoIDs; convert Unix timestamps; read cron expressions and their next runs; diff two texts; turn CSV and YAML into JSON and JSON into TypeScript; format SQL, HTML, CSS and JavaScript; minify; make lorem ipsum; send HTTP requests; convert case, HTML entities and number bases; preview Markdown, format XML, sort and de-duplicate lines, escape strings, see text as hex, try HTML in a playground, look up HTTP status codes, read user agents and keycodes, and work out chmod, subnets, px to rem and aspect ratios. Free with no size limits, works offline.
Free to use. Optional one-time upgrade: Dev Tools Pro, $1.99 (no subscription), or every upgrade in every Yuzool app with Yuzool Plus, $19.99 once. Works on iPhone, Android, Mac and PC; add it to your Home Screen to open it like an app.
Guide: How to decode a JWT safely, and check its signature
Also on Yuzool: JSON formatter and validator · Regex tester · JWT decoder · Base64 encode and decode · URL encode and decode · Hash generator · UUID generator · Unix timestamp converter · Cron expression explainer · Diff checker · CSV to JSON converter · YAML to JSON converter · JSON to TypeScript · SQL formatter · Code formatter · Minifier for HTML, CSS and JavaScript · Lorem ipsum generator · HTTP request tester · Case converter · HTML entities encoder and decoder · Number base converter · XML formatter and validator · Markdown preview · Sort lines and remove duplicates · String escape and unescape · Text to hex and binary · HTML playground · HTTP status codes · User agent parser · JavaScript keycode viewer · Chmod calculator · Subnet calculator · Px to rem converter · Aspect ratio calculator