Guides

Short, practical explanations of the formats and ideas behind our tools.

• How to Read a JWT: Header, Payload and Claims Explained

  Learn how to read a JSON Web Token: what the header, payload and signature mean, what exp, iat and nbf do, and why decoding is not verifying.

• Unix Timestamps Explained: Seconds, Milliseconds and the Year 2038

  What a Unix timestamp is, how to tell seconds from milliseconds, how to convert to a date in Excel, JavaScript, Python and SQL, and what the year 2038 problem means.