JWT Decoder & Inspector — Free Client-Side Tool

100% Client-Side. Tokens & secrets never leave your browser.

Samples:

Encoded JWT Token

HEADER.PAYLOAD.SIGNATURE

Signature Verification Decoded (Unverified)

HMAC verification uses Web Crypto SubtleCrypto in-browser.

SECURITY WARNING: Token algorithm is set to "none". This token is completely unsigned and insecure!

Standard Claims Inspector 0 claims

Paste a valid token to inspect claims.

HEADER: Algorithm & Token Type

// Header JSON will appear here

PAYLOAD: Data Claims

// Payload JSON will appear here

1. Configure Header & Payload JSON

HEADER JSON

PAYLOAD JSON

HMAC SHA-256 SECRET

2. Generated Signed JWT Token