Practical guide
JWT exp Timestamp Converter: Check Token Expiration Time
JWT time claims such as exp, iat, and nbf are usually Unix timestamps in seconds. Converting them into readable dates helps you quickly understand whether a token is expired, not yet valid, or issued at the expected time.
Open the free toolStep-by-step
- Decode the JWT and find the exp, iat, or nbf claim.
- Copy the numeric timestamp without quotes or commas.
- Open the Unix timestamp converter.
- Select seconds if the value has 10 digits, or milliseconds if it has 13 digits.
- Compare the local time and UTC result with your application logs.
- Remember that expiration also depends on your backend validation rules.
Important tips
- JWT timestamps are normally seconds, not milliseconds.
- If the converted date is far in the future, you may have selected the wrong unit.
- A token can decode correctly and still be rejected because of signature, issuer, audience, or clock-skew checks.
- Use UTC when comparing values with server logs.
Frequently asked questions
What does exp mean in JWT?
The exp claim is the time after which the token should be rejected.
Is JWT exp in seconds or milliseconds?
JWT NumericDate values are normally Unix timestamps in seconds.
Can I check JWT expiration without verifying the signature?
You can inspect the timestamp, but you should not trust the token until the signature and claims are verified.