🛡️ 100% Browser Local Execution · Zero Upload Privacy · Instant Speed
Client-Side JWT Decoder & Debugger
Decode JWT Header and Payload locally, check token expiration (exp/iat/nbf) countdown, and verify HMAC-SHA256 signatures.
📖 How to Use & Technical Guide
- Paste your encoded JWT string (eyJ...) into the token input box.
- Inspect the decoded JSON Header, Payload claims, and automatic expiration status badge.
- Optionally enter your HMAC-SHA256 secret key to verify whether the signature is authentic.
❓ Frequently Asked Questions
Is it safe to paste production JWTs here?
Yes. Unlike traditional debuggers that log analytics or sync state, our JWT decoder runs 100% client-side with zero network requests.