FullCalculator

JWT Token Decoder

JWT Token Decoder

Free JWT (JSON Web Token) decoder

Formula

JWT = Base64Url(Header).Base64Url(Payload).Signature

Frequently Asked Questions

What is a JWT?
JSON Web Token — a compact, URL-safe token format for securely transmitting claims. Used for authentication and API authorization. Format: header.payload.signature.
Is it safe to decode JWTs online?
Decoding only reveals the payload — it doesn not verify the signature. This tool runs entirely in your browser, but avoid pasting production tokens with sensitive data into any online tool.