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JWT Decode
Decode JWT headers and payloads locally for quick inspection without remote processing.
Security notice
- This decoder only reads the token. It does not validate signature or authenticity.
- Everything runs in your browser. Paste tokens only in trusted environments.
Processed locally
LocalAuto
Input
JWT token
Output
Process the input to see the result here.
About this tool
Decode JWT headers and payloads locally for quick inspection without remote processing.
Standard tool execution runs in the browser, with no dedicated backend for processing inputs.
How to use
- Paste or enter data in the input panel.
- Use Process, or let automatic processing run when available.
- Review the result, copy the output, and validate it before critical use.
Common use cases
- Inspect authentication claims
Quick examples
Inspect authentication claims
Input: Bearer eyJhbGciOi...
Output: Readable JSON for header and payload.
JWT Decode FAQ
Does JWT Decode validate token signature?
No. It only decodes header and payload and does not validate authenticity.
Is my token sent to a backend?
No. Processing stays local in the browser.
Can I paste tokens with Bearer prefix?
Yes. Bearer prefix is removed automatically before decoding.
Is there a token size limit?
Yes. The limit is up to 16 KB after normalization.
When do I get invalid token errors?
When the token is not valid JWT shape (3 segments) or decoding fails.
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