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JWT Decoder Online Free

Free online JWT decoder tool to read token header and payload claims for developers.

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Free online JWT decoder tool to read token header and payload claims for developers.

How it works

JWT Decoder parses header and payload claims for inspection during authentication debugging and API testing. It helps verify claim values like exp, aud, and iss quickly. Decoding does not verify cryptographic signature validity.

Example

Input:
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjMifQ.signature

Output:
Header: {"alg":"HS256","typ":"JWT"}
Payload: {"sub":"123"}

FAQ

Does decoding prove a JWT is valid?

No. You must verify signature, issuer, audience, and expiration with trusted keys and server-side checks.

What claims should I review first?

Start with exp, nbf, aud, iss, and sub to catch most auth misconfiguration issues.

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