Encoding
JWT Decoder
Decode JSON Web Tokens to inspect the header, payload and signature — verify claims and expiry in-browser.
Paste a JWT above to inspect its header and payload.
Why use our JWT Decoder?
100% private
Everything runs in your browser. Your data never leaves your device — safe for production payloads.
Instant results
No round trips, no rate limits, no login. Format, validate and inspect megabytes of JSON in milliseconds.
Standards-first
Follows RFC 8259 / ECMA-404 exactly. Reports errors with precise line and column diagnostics.
Related developer tools
Base64 to JSON
Decode a Base64-encoded JSON payload and pretty-print the result. Perfect for JWT payload inspection.
OpenJSON Unescape
Unescape a JSON string literal back to plain text — reverses \n, \", \uXXXX and other escapes.
OpenJSON URL Decode
URL-decode a percent-encoded JSON string and pretty-print the parsed structure.
OpenBase64 Encoder / Decoder
Encode or decode Base64 payloads with UTF-8 support. Handy for JWTs, data URIs and binary transport in JSON.
OpenCSV Unescape
Reverse CSV field quoting — strips surrounding quotes and unescapes doubled quotes.
OpenHTML Unescape
Decode HTML entities back to characters — supports & < numeric ' and hex ' forms.
OpenRelated reading
Deep-dive guides that pair well with the JWT Decoder.
Developer Tips
10 common JSON errors and how to fix them
Every JSON syntax error you'll ever see — trailing commas, unquoted keys, bad escapes — with a working repair strategy.
ReadGuides
What is JSON? A developer's introduction
Understand the JSON data format, its history, and why it dominates modern APIs and configuration files.
ReadComparisons
JSON vs XML: which should you use?
Compare readability, verbosity, tooling, schema support and performance between JSON and XML in modern systems.
Read