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HomeToolsSecurityJWT Builder & Signer

JWT Builder & Signer

Free

Build and sign JWTs with HS256/384/512. Verify signatures. Runs in your browser.

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About JWT Builder & Signer

Build, sign, and verify JSON Web Tokens (JWT) entirely in your browser. Choose HMAC algorithm (HS256, HS384, or HS512), set any standard or custom claims, enter a secret key, and get a signed JWT instantly. Switch to Verify mode to validate any JWT signature. Uses the Web Crypto API — your secret never leaves your device.

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Claims

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All signing and verification runs locally via the Web Crypto API. Your secret never leaves your browser.