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How to use JWT Generator (HS256)

Edit the header and payload JSON, enter a secret, and the tool Base64URL-encodes both segments and signs them with HMAC-SHA256 to produce a complete JWT.

Frequently asked questions

What is HS256?

HMAC using SHA-256 — a symmetric signing algorithm where the same secret both signs and verifies the token.

How do I verify the generated token?

Paste the token and the same secret into jwt.io or a JWT debugger; a matching signature confirms it was signed correctly.

Should I use this for production tokens?

Use it for testing and learning. In production, generate and sign tokens server-side so the secret is never exposed to the browser.

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