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AiTechWorlds
AiTechWorlds
Build and sign JWT tokens with HS256 using Web Crypto API — header, payload, and secret.
Header
Payload
Standard Claims
Custom Claims
Secret
The JWT Builder creates signed JSON Web Tokens using HMAC-SHA256 (HS256) entirely in your browser via the Web Crypto API. Set the payload claims (sub, iat, exp, and custom key-value pairs), enter your signing secret, and get a properly signed JWT. Pairs with the JWT Decoder tool for verification.
Set claims
Add key-value pairs to the payload. Enable iat (issued at) and exp (expiry) as needed.
Enter secret
Type your HMAC secret, or click Generate to create a random one.
Sign the token
Click Sign JWT to generate the signed token. Copy it to use in your application.
100% Private — No Server Required
All processing happens directly in your browser. No data is uploaded, stored, or transmitted to any server.
Last reviewed on June 5, 2026 by the AiTechWorlds Tools Team. All processing runs locally in your browser.
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