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JWT Secret Generator

Generate JWT HMAC secrets using secure browser randomness.

JWT Secret Generator
Generate HMAC signing secrets using Web Crypto. Store generated secrets securely.

This tool generates secret material without saving or sending it. Never commit production secrets to a repository.

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Practical guide

Generate random material for HMAC signing in 256, 384 or 512-bit lengths, formatted as hex or Base64URL. The tool creates a secret value; it does not create or verify JWTs.

How to use it

  1. Select the strength required by your service; 256 bits is a sensible starting point if you are unsure.
  2. Choose an output format compatible with your secret configuration.
  3. Generate, copy and promptly store the value in a protected secret manager.

Example

For an HS256 development environment, create a 256-bit value and put it in a server-side environment variable, never in client code or a Git commit.

What to know

Hex and Base64URL are encodings. How a server reads the string determines the actual key bytes it uses. This page does not persist generated output; a refresh removes it.

Common question

Can I put this value in a front-end app?

No. An HMAC signing secret must remain on a trusted server or in a secret-management system.

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