Support & Help

JWT tools support and FAQ. Fix JWT not decoding, invalid signature errors, and expired token issues. Links to decoder, validator, and guides.

Find answers to common JWT problems below. For anything else, email support@ratpdf.com.

Quick Links

JWT Decoder Decode tokens instantly JWT Validator Verify signatures JWT Basics Guide Learn token structure Malformed JWT Fix decode errors Invalid Signature Diagnose verify failures Expired Token Fix Handle exp errors

FAQ

Why is my JWT not decoding?

A valid JWT must have exactly three Base64URL segments separated by dots (header.payload.signature). Check for truncation, extra whitespace, or non-JWT strings. Use our JWT Decoder tool and see our malformed JWT error guide.

How do I fix an invalid signature error?

Verify you're using the correct secret or public key, matching the algorithm in the token header (alg claim). For RS256, use the JWKS Validator with your issuer's JWKS endpoint.

My token is expired — what now?

The exp claim indicates expiration. You cannot extend it client-side. Use a refresh token to obtain a new access token from your auth server. See our JWT Expired Token Fix guide.

Are my tokens safe on this site?

Yes. All processing happens in your browser. Tokens are never uploaded to our servers. See our Privacy Policy for details.

Can I use these tools offline?

Once loaded, most tools work offline since they require no server API calls (except optional JWKS fetch).

Still Need Help?

Email our support team at support@ratpdf.com. We respond within 2–3 business days.