JWT signature verifier
Verify an HS256 JWT with a supplied secret.
How it works & limits
How to use this tool
Verify an HS256 JWT with a supplied secret.
Enter your content or open a file, then select Run.
Example input
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJkZW1vIn0.VRsgtLbHmcl48FiMGNUl-lyKanB-fhLLMmR6nNxzjiU
Local processing
Your input stays in this browser. Drafts are kept in page memory while switching tools, and disappear on reload.
Text is limited to 1 million characters. Regex runs in a worker, capped at 200,000 characters, 1,000 matches and 1.5 seconds. Inputs above 100,000 characters use manual refresh.
The first page load and on-demand modules require network access. A complete offline cache is not included.