JWT Debugger & Inspector
Decode JSON Web Tokens and inspect claims locally in your browser (100% Private, Zero Network Calls).
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How to Decode and Debug JSON Web Tokens (JWT) Privately
JSON Web Tokens (JWT) are the industry standard for stateless authentication in web applications. Debugging JWT tokens often involves pasting sensitive authorization headers. RetroBox JWT Debugger runs 100% in your browser so confidential user claims and API keys are never exposed to external logging servers.
⚡ STEP-BY-STEP INSTRUCTIONS:
Paste your encoded JWT string (e.g. `eyJhbGciOiJIUzI1Ni...`) into the input box.
Instantly view the decoded Header (algorithm & type) and Payload claims (user ID, permissions, expiration `exp`).
Enter your secret key or public RSA key to verify signature validity in real time.
❓ FREQUENTLY ASKED QUESTIONS (FAQ):
Q: Is it safe to paste production JWT tokens here?
Yes! Unlike other online JWT decoders that send your tokens over HTTP to backend servers, RetroBox decodes tokens 100% locally using client-side JavaScript Base64URL decoding.
Q: What algorithms are supported for signature verification?
Supports symmetric HMAC algorithms (HS256, HS384, HS512) and asymmetric RSA / ECDSA algorithms.
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