JWT boundaries explained

Decode JWTs without mistaking data for trust

Practical guides distinguish compact serialization, strict parsing, signature verification and application authorization.

Trust boundary6 min read

JWT decoding is not signature verification

Understand why readable claims remain attacker-controlled until cryptographic and application checks succeed.

Format6 min read

Follow the exact transformations behind a three-part compact JWT and the malformed inputs strict tools should reject.

Time claims6 min read

Convert exact epoch seconds without turning a local display into a verdict about token validity.