JWT Expiry Checker Online
Check JWT token expiry status, time remaining, and inspect standard claims (exp, iat, nbf, iss, sub, aud).
What Is JWT Expiry Checker?
JWT Expiry Checker is a free browser-based tool that decodes JSON Web Tokens and instantly reports their expiry status. Paste any JWT and see whether it is valid, expired, or not yet active — together with a live countdown showing exactly how much time remains (or how long ago it expired). It also surfaces all standard claims: exp (expiration), iat (issued at), nbf (not before), iss (issuer), sub (subject), and aud (audience). All processing is done locally in your browser — no token data is ever sent to a server.
How to Use JWT Expiry Checker
- Paste your JWT token into the input area, or click Load Sample.
- The status banner immediately shows whether the token is valid, expired, or has no expiry set.
- The claims table displays exp, iat, and nbf as human-readable dates, with colored badges showing validity state.
- The algorithm and token type are shown at the bottom.
- Click Copy to copy the decoded payload as formatted JSON.
Features
- Instant expiry status — green/yellow/red banner with exact time remaining or elapsed
- Standard claims display — exp, iat, nbf shown as ISO dates with status badges
- Issuer, subject, audience — iss, sub, aud claims displayed in the claims table
- Algorithm detection — shows the signing algorithm (HS256, RS256, etc.) and token type
- No-expiry warning — flags tokens missing the exp claim as a potential security concern
- Privacy-first — all decoding is local, nothing is uploaded or logged
FAQ
What does JWT Expiry Checker do?
JWT Expiry Checker decodes a JWT token and checks the exp (expiration), iat (issued at), and nbf (not before) claims. It shows whether the token is currently valid, expired, or not yet active, along with a human-readable countdown.
What is the exp claim in a JWT?
The exp (expiration time) claim is a Unix timestamp after which the JWT must not be accepted for processing. For example, exp: 1700000000 means the token expires at that UTC timestamp.
What happens if a JWT has no exp claim?
A JWT without an exp claim does not expire by default. This tool will show a warning indicating no expiry is set, which is a potential security concern depending on your use case.
Is my JWT token sent to your server?
No. All decoding and expiry checking happens entirely in your browser using JavaScript. No token data is transmitted anywhere.