Developer tools
Format JSON, decode JWTs, encode Base64 and URLs, generate UUIDs and hashes. Everything runs in your browser, so tokens and data stay private.
- JSON formatter and validator
Format, validate and minify JSON in your browser. Clear errors with line and column, big numbers kept exact, duplicate keys flagged. No upload.
- JWT decoder and verifier
Decode a JWT to read its header, payload and expiry, and check its signature with a secret or public key. Runs in your browser; the token stays private.
- Base64 encoder and decoder
Encode text or files to Base64 and decode Base64 back, with proper UTF-8, URL-safe Base64 and file detection. Free, in your browser, no upload.
- URL encoder and decoder
Percent-encode text for URLs and query strings, or decode %20-style escapes back to text. Handles UTF-8, + for spaces and splits URLs into parts.
- UUID generator
Generate UUID v4 or v7 values, one or a thousand at once, with the browser’s secure random generator. Check any UUID’s version and creation time.
- Hash generator and checksum checker
Calculate MD5, SHA-1, SHA-256, SHA-384 and SHA-512 hashes of text or files, and check a download against its checksum. In your browser, no upload.