JWT Validator
Verify HS256 and RS256 signatures and validate exp, nbf, aud and iss claims
Expected claims
Allows small clock differences when checking exp and nbf.
Decode-only inspection: JWT Decoder · Sign test tokens: JWT Signer
About this tool
Validate JWT signatures and exp/nbf/aud/iss claims online. Free, private, pairs with JWT Decoder — runs in browser. JWT Validator runs in the browser on DevTools. There is no signup, and your input stays on this device unless the tool explicitly performs a live network lookup.
What this tool does not do
- JWT Validator is a free in-browser utility, not a hosted API. It does not keep server-side history and is not a substitute for production verification in your own stack.
How do I use this tool?
How do I use JWT Validator?
Open JWT Validator, enter or paste your input, and copy the result. The page works without an account.
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