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Tool Factory

Keys, Certificates & Tokens

JWT Signer

Process key or token data with JWT Sign and explicit format settings. Enter the key material, choose the required format, then review the result.

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Process key or token data with JWT Sign and explicit format settings. Enter the key material, choose the required format, then review the result.

This tool runs open-source code from CyberChef by GCHQ (Apache License 2.0). See open-source credits.

JWT Signer performs JSON Web Token creation for the supplied key or certificate data. It serializes and signs JSON claims into a compact token. Header and payload remain readable without the signing key.

It serializes and signs JSON claims into a compact token. Header and payload remain readable without the signing key. This result runs in the browser for this catalog category. Processing runs in the browser.

JWT operations encode or check signed claims; application authorization and token lifecycle remain outside this tool.

Instructions

  1. Provide text or data for this tool.
  2. Choose the receiving application's expected algorithm before signing. This applies to JWT Signer.
  3. Use a disposable token and its matching secret in JWT Verify. This applies to JWT Signer.

Example

Input: Use JSON {"sub":"demo"}, Signing algorithm HS256, Private/Secret Key "public-test", and Header {}.

Settings: JWT Signer: Private/Secret Key accepts a shared HMAC secret or an appropriate private PEM key. Signing algorithm and Header configure token creation.

Result: It serializes and signs JSON claims into a compact token. Header and payload remain readable without the signing key.

Limits

  • JWT Signer: Do not select None when a receiving system requires an authenticated token.
  • JWT Signer: Signing does not automatically establish valid issuer, audience, or access policy.

Questions

What input does JWT Signer accept?

JWT Signer accepts a structured JSON value.

Which settings does JWT Signer provide?

JWT Signer provides controls for Private/Secret Key, Signing algorithm, Header.

What does JWT Signer return?

JWT Signer returns text. Signs a JSON object as a JSON Web Token using a provided secret / private key. The key should be either the secret for HMAC algorithms or the PEM-encoded private key for RSA and ECDSA.