JWT Decoder Online
Decode JSON Web Tokens instantly. Verify signatures, inspect claims, and learn about JWT security. Supports HMAC, RSA, and ECDSA algorithms.
Frequently Asked Questions
What is a JWT Decoder?
A JWT decoder is a tool that allows you to decode and inspect JSON Web Tokens (JWT). JWTs are commonly used for authentication and authorization in web applications. A decoder lets you see the header, payload, and signature of a JWT without needing to write code.
Is this JWT Decoder free to use?
Yes, our JWT Decoder is completely free to use. No signup or registration is required. Simply paste your token and decode it instantly.
What algorithms are supported?
We support multiple JWT algorithms including HS256, HS384, HS512 (HMAC), RS256, RS384, RS512 (RSA), ES256, ES384, ES512 (ECDSA), and PS256/384/512 (RSA-PSS).
Is my JWT data secure?
Yes. All decoding happens locally in your browser. Your tokens are never sent to our servers. We do not store, log, or transmit any JWT data you decode.
What's the difference between decode and verify?
Decoding simply converts the Base64URL-encoded token back to its JSON form. Verification also checks the cryptographic signature to ensure the token hasn't been tampered with. We show both the decoded content and validation status.
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