Question 1

What is a JWT?

Accepted Answer

A JWT (JSON Web Token) is a compact, URL-safe way to represent claims between two parties — commonly used for authentication and authorization. It has three Base64URL-encoded parts separated by dots: a header (algorithm and token type), a payload (claims like user ID, issued time, and expiry), and a signature.

Question 2

Is it safe to paste my JWT into this decoder?

Accepted Answer

Decoding happens entirely in your browser using JavaScript — the token is never sent to any server, including QikDrive’s. That said, JWTs often contain sensitive session information, so avoid pasting tokens from production systems into any third-party tool, including this one, unless you trust it runs locally (you can verify this by checking your browser’s network tab — no requests are made).

Question 3

Can this tool verify a JWT’s signature?

Accepted Answer

No. Verifying a signature requires the secret key (for HMAC algorithms like HS256) or the public key (for RSA/ECDSA algorithms like RS256/ES256), which this tool never asks for or has access to. It only decodes and displays the header and payload — it does not verify authenticity.

Question 4

What do the exp, iat, and nbf claims mean?

Accepted Answer

"iat" is when the token was issued, "exp" is when it expires, and "nbf" is "not before" — the token isn’t valid until that time. All three are Unix timestamps (seconds since epoch); this decoder converts them to readable dates automatically.

Question 5

Why is my decoded token showing an error?

Accepted Answer

A valid JWT has exactly three Base64URL-encoded segments separated by dots (header.payload.signature), and the header/payload must decode to valid JSON. If you’re seeing an error, double check you’ve copied the complete token without extra spaces, quotes, or a "Bearer " prefix.

JWT Decoder

Free JWT Decoder

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Readable timestamps

Expiry at a glance

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