Developer Tools
JWT Decoder — Inspect Token Payload, Nothing Leaves Your Browser
🔒 Runs in your browser
Decode any JWT's header and payload instantly to inspect claims, timestamps, and metadata. Your token never leaves your browser — critical since JWTs are credentials. No server, no account, no tracking.
How to use this tool
- Paste a JWT token into the input field.
- The header and payload are decoded and displayed instantly.
- Inspect claims, expiry timestamps, and issuer information.
Next step
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Frequently Asked Questions
- Does this verify the signature?
- No. It decodes the header and payload for inspection only. Signature verification requires the secret or public key and should be done server-side.
- Is my token sent to a server?
- No. Decoding happens entirely in your browser. Your token never leaves your device — important, since tokens are sensitive credentials.
- What do iat and exp mean?
- iat is the issued-at time and exp is the expiry time, both as Unix timestamps. This tool shows them in human-readable UTC.
- Why is my token shown as invalid?
- A JWT must have exactly three Base64URL-encoded parts separated by dots: header.payload.signature.
How to Decode a JWT Without a Third-Party Tool (2026)
Decode JSON Web Tokens locally in your browser for debugging — no upload, no external tools, no copying tokens to untrusted websites.