Developer Tools
Utilities for everyday development work: format and validate JSON, decode JWTs, generate UUIDs, encode and decode Base64 and URLs, convert timestamps, and more. Everything runs locally in your browser.
Tools in Developer Tools
JSON Formatter
Format, beautify, and validate JSON with adjustable indentation — instantly in your browser.
JSON Validator
Check whether your JSON is valid and find the exact line and column of any syntax error.
UUID Generator
Generate cryptographically random UUID v4 identifiers, one or a thousand at a time.
Base64 Encoder
Encode any text — including emoji and non-Latin scripts — into standard Base64.
Base64 Decoder
Decode Base64 back into readable text, with clear errors for malformed input.
URL Encoder
Percent-encode text for safe use in URLs — as a query value or a full URL.
URL Decoder
Decode percent-encoded URLs and query strings back into readable text.
JWT Decoder
Decode a JWT’s header and payload and check its expiration — without sending it anywhere.
Unix Timestamp Converter
Convert Unix timestamps to readable dates and back, with a live current-time readout.