JWT Decoder
Decode JSON Web Tokens (JWT) to inspect headers and payload data. Debug authentication issues instantly.
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Applications & Usability
Authenticating a user but not sure what claims are being sent? Our JWT Decoder allows you to decode and inspect any JSON Web Token instantly. It breaks the jwt into its three fundamental parts—Header, Payload, and Signature—allowing you to view user IDs, expiration times, and custom roles without needing the secret key used for server-side verification.
Calculation Methodology
When working with auth systems like OAuth2 or OpenID Connect, verifying the contents of your token is critical for troubleshooting "unauthorized" errors. This tool provides a clean, formatted view of the jwt data, making it easy to spot expired timestamps or incorrect scope declarations. It is a strictly client-side utility, ensuring your sensitive authentication data never leaves your browser.
Fun Fact: Security Reminder: Decoding a JWT only reveals the information; it does not prove the token is valid! Always verify the signature on your backend before trusting the data.
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