JWT Claims Explained With a Live Decoder
Learn what every registered JWT claim means: iss, sub, aud, exp, nbf, iat and jti. Paste a token to see each claim decoded.
Part of the free JWT Decoder. Runs in your browser — nothing is uploaded.
JWT Claims Explained With a Live Decoder
RFC 7519 defines seven registered claims: iss, sub, aud, exp, nbf, iat and jti. They are all optional but widely used. The example shows all of them in one token, with the time claims converted to dates.
Worked example: A token using every registered claim
JWT
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJodHRwczovL2F1dGguZXhhbXBsZS5jb20iLCJzdWIiOiJ1c2VyXzEiLCJhdWQiOiJhcGkuZXhhbXBsZS5jb20iLCJleHAiOjE3NjcyMjkyMDAsIm5iZiI6MTc2NzIyNTYwMCwiaWF0IjoxNzY3MjI1NjAwLCJqdGkiOiJjN2YzYjFlMi01ZDQ0LTRhOGUtOWI4YS0yZjZkMWUwYTdjMTEifQ.c2lnbmF0dXJl
Decoded token
// HEADER
{
"alg": "HS256",
"typ": "JWT"
}
// PAYLOAD
{
"iss": "https://auth.example.com",
"sub": "user_1",
"aud": "api.example.com",
"exp": 1767229200,
"nbf": 1767225600,
"iat": 1767225600,
"jti": "c7f3b1e2-5d44-4a8e-9b8a-2f6d1e0a7c11"
}
// CLAIM TIMES (UTC)
iat: 2026-01-01 00:00:00 UTC
nbf: 2026-01-01 00:00:00 UTC
exp: 2026-01-01 01:00:00 UTCPractical tip
Use jti to implement token revocation. Store revoked IDs until their exp passes and reject any token whose jti is on the list.
How to use this JWT Decoder
- 1Use the live tool above — it runs entirely in your browser and never uploads your data.
- 2Paste the sample from the worked example, or use your own input.
- 3Copy the result, then adapt the same steps in your editor, script, or pipeline.
JWT Claims Explained With a Live Decoder FAQs
Are JWT claims required?
The registered claims are optional by the spec, but for security you should always set and check exp, iss and aud.
What does jti mean?
jti is the JWT ID, a unique identifier for the token. It helps prevent replay and lets you revoke individual tokens.
More JWT Decoder pages
- Decode a JWT Token OnlineDecode a JWT token online to read its header and payload claims. Paste the token and see readable JSON instantly. Runs in your browser, nothing is uploaded.
- JWT Expiration CheckerCheck when a JWT expires. Paste the token to read the exp claim as a human-readable UTC date and see if your access token is still valid.
- Decode a JWT Without the SecretYou can decode a JWT without the secret because the header and payload are only Base64URL encoded. Paste a token to read it. Verification needs the key.
- JWT Payload ViewerView the JWT payload and its claims such as iss, aud and sub. Paste a token to inspect who issued it, who it is for and what scopes it carries.
- Decode an Auth0 JWTDecode Auth0 ID tokens and access tokens to inspect claims like iss, aud, scope and custom namespaced claims. Free, local and private.
- Decode a Firebase ID TokenDecode a Firebase Authentication ID token to inspect uid, email, auth_time and sign-in provider claims. Free browser-based Firebase JWT decoder.
- Decode an AWS Cognito JWTDecode AWS Cognito ID and access tokens. Inspect token_use, cognito:groups, client_id and username claims. Free local JWT decoder.
- JWT Header and Algorithm CheckerCheck a JWT header for the alg, typ and kid fields. Find out whether a token is signed with HS256 or RS256 and which key ID to verify with.
- JWT nbf (Not Before) Claim CheckerCheck the JWT nbf claim. See the "not before" time as a readable UTC date and find out why a fresh token is rejected as not yet valid.