Developer Tool
JWT Decoder
Decode JSON Web Tokens locally in your browser. View header, payload, claims, and expiry status without sending data anywhere.
Your data is processed locally in your browser and is never uploaded.
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FAQ
- Does this tool verify JWT signatures?
- No. This tool decodes the token only. It does not verify the signature or authenticity. Never paste tokens containing sensitive data into online tools.
- Is my JWT sent to a server?
- No. All decoding happens locally in your browser using JavaScript. No data leaves your device.
- What JWT formats are supported?
- Any standard JWT with three Base64URL-encoded dot-separated parts (header.payload.signature). Supports Unicode payloads.
- How are timestamps displayed?
- The iat, exp, and nbf claims are automatically converted to human-readable ISO 8601 dates with expiry status.