JWT Decoder

Paste a JWT token to instantly decode the Header, Payload, and Signature — and check its expiry status

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JWT input

Decoded output

Paste a three-part JWT on the left and click Decode to see the Header, Payload, and signature segment here.

Paste the token

Paste the full three-part JWT in the left panel, or use Paste to pull text from your clipboard.

Decode

Click Decode in the toolbar, or paste into the field to decode automatically.

Review and copy

The right panel shows the algorithm, expiry state, and each section; use Copy to grab plain text for that block.

Reminder: this tool only decodes content. It does not verify signatures, so do not treat a successful decode as proof the token is trustworthy.

When is this tool useful?

When you are developing or debugging and need to quickly see what data a JWT carries, whether it is expired, or which algorithm the header declares—all locally in your browser without sending the token to our servers.

If I can decode a JWT, does that mean the token is authentic?

No. Anyone can decode the three segments and read the JSON. Authenticity requires cryptographic signature verification with a secret or public key on a server. This tool does not perform verification.

Is my token uploaded to your servers?

No. Decoding runs entirely in your browser; your pasted token is not sent in network requests to us.

Why do some times appear as readable dates while the Payload still shows numbers?

The standard-claims area converts common time fields into dates for quick reading. The full Payload is still shown as raw JSON, so timestamps may remain numeric there—use both views together.

What does it mean if the algorithm implies no signature protection?

It suggests the token may not be integrity-protected, so content could be forged. Production systems should reject such configurations and use signed tokens with proper verification.

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