Question 1

What is a JWT token?

Accepted Answer

JWT (JSON Web Token) is a compact, URL-safe means of representing claims to be transferred between two parties. It consists of three parts: Header, Payload, and Signature, separated by dots.

Question 2

Is it safe to decode my JWT token here?

Accepted Answer

Yes! All decoding happens entirely in your browser using client-side JavaScript. Your tokens are never sent to any server. For added security, we recommend not using production tokens with sensitive data.

Question 3

What does the expiration time mean?

Accepted Answer

The "exp" (expiration time) claim identifies the expiration time on or after which the JWT must not be accepted for processing. Our visual timeline shows you exactly when your token expires and how much time is remaining.

Question 4

Can I validate the signature?

Accepted Answer

Yes! For HS256 (HMAC) signed tokens, you can enter your secret key to verify the signature. Note that RS256 and other public-key algorithms are not yet supported in the browser.

Question 5

What are the common JWT claims?

Accepted Answer

Common claims include: "iss" (issuer), "sub" (subject), "aud" (audience), "exp" (expiration time), "nbf" (not before), "iat" (issued at), and "jti" (JWT ID). Custom claims can also be added.

Question 6

Why is my token showing as expired?

Accepted Answer

Your token is expired if the current time is past the "exp" (expiration) timestamp. Expired tokens should not be accepted by services. You'll need to obtain a new token from your authentication service.

Question 7

Can I download the decoded token?

Accepted Answer

Yes! Use the download button to export the decoded header, payload, validation results, and timeline data as a JSON file for your records or debugging purposes.

Question 8

Does JWT Debugger Pro store my tokens?

Accepted Answer

Only in your browser's localStorage for convenience (so you can refresh the page). We never send your tokens to any external server. You can clear your token anytime using the Clear button.

JWT Debugger Pro

Decode & Debug JWT Tokens

Visual Timeline

Human-Readable

Smart Validation

Real-Time

Frequently Asked Questions