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JWT Signer / Verifier

Create HMAC JWTs, verify signatures with a secret, and inspect decoded claims.

Quick context
  • Runs entirely client-side with no server dependency.
  • Built for copy-paste workflows and fast iteration.
  • Optimized for desktop and mobile editing sessions.
jwtsignverify

JWT header

Provide a JSON object. alg and typ are normalized during signing.

JWT payload

Payload claims are signed with the selected HMAC algorithm.

JWT token

Paste any JWT here to decode and verify it with the current secret.

Signature
Valid
Signature matches the provided secret.
Algorithm
HS256
Only HMAC JWTs are supported for signing and verification.
Expiration
Present
2030-01-01T00:00:00.000Z
Encoded signature

sdjhYg5X-Nd6zk0JxWvW08e6XLRHF17Ln7CsddJ64pU

Expected signature

sdjhYg5X-Nd6zk0JxWvW08e6XLRHF17Ln7CsddJ64pU

Decoded JWT

Decoded header and payload from the current token.