Encoding
Base64 to JSON
Decode a Base64-encoded JSON payload and pretty-print the result. Perfect for JWT payload inspection.
Output will appear here…Why use our Base64 to JSON?
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
JSON to Base64
Convert JSON to a compact Base64-encoded string. Great for embedding JSON in URLs, cookies or headers.
OpenBase64 Encoder / Decoder
Encode or decode Base64 payloads with UTF-8 support. Handy for JWTs, data URIs and binary transport in JSON.
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.
OpenJWT Decoder
Decode JSON Web Tokens to inspect the header, payload and signature — verify claims and expiry in-browser.
OpenCSV Unescape
Reverse CSV field quoting — strips surrounding quotes and unescapes doubled quotes.
OpenRelated reading
Deep-dive guides that pair well with the Base64 to JSON.
Guides
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.
ReadDeveloper 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.
Read