JWT Decoder
Decode JWT header and payload online — inspect algorithm, claims, and expiry without verifying the signature.
About this tool
Inspect JSON Web Tokens by decoding the header and payload segments for API debugging and auth troubleshooting. See algorithm, expiry, and common claims with human-readable dates — signature is shown but not verified.
What you get
- Decoded JWT header JSON (alg, typ, kid, …)
- Decoded payload claims with exp, nbf, and iat as readable dates
- Expired or not-yet-valid indicators on time claims
- Raw signature segment (base64url) for reference
- Parse errors for malformed or incomplete tokens
- Copy buttons for header, payload, or full token parts
How to use
Paste a JWT (three base64url parts separated by dots). Review header and payload JSON — do not treat the result as proof the token is valid.
Example
Inspect claims and expiry locally — decoding does not verify the signature.
Input
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkRldiBVc2VyIn0.signature
Output
Header: {"alg":"HS256","typ":"JWT"}
Payload: {"sub":"1234567890","name":"Dev User"}
Related searches
- jwt decoder
- decode jwt
FAQ
How to decode a JWT token online?
Paste the three dot-separated Base64url segments. Header and payload JSON appear with human-readable dates for time claims.
What information is in a JWT payload?
Typical claims include subject, issuer, audience, expiration (exp), issued-at (iat), and custom app fields—all visible after decoding.
Can I verify a JWT signature with a decoder?
Decoding shows the signature segment but does not prove the token is authentic. Verification requires the issuer's secret or public key.
What do exp, iat, and nbf claims mean?
exp is expiration time, iat is issued-at, and nbf is not-before. The tool flags tokens that are expired or not yet valid.
How to check if a JWT access token is expired?
Paste the token and read the exp claim with the human-readable expiry row—expired tokens are flagged without needing the signing secret.
By using this tool you agree to our Terms of Use and Privacy Policy. Results are provided as-is without warranty.