About The JWT Encoder (HS256)

JWT Encoder creates signed HS256 JSON Web Tokens from a payload and shared secret. It is useful for local API testing, demo tokens, and controlled integration fixtures.

Signing runs locally in your browser with Web Crypto when available. The tool creates HS256 tokens only; use another workflow for RSA or ECDSA signing.

How to Encode JWTs Online

1. Paste valid JSON into the payload field.
2. Enter the shared secret for HS256 signing.
3. Generate the token and copy it into your test request or fixture.

Choosing Options Correctly

Use the default header for most HS256 tests. Advanced header editing is only for cases where you need custom metadata; the algorithm is forced to HS256.

Common Use Cases

• Creating local bearer-token fixtures.
• Testing middleware that expects signed HS256 tokens.
• Building reproducible examples for API documentation.

Quick FAQ

Can this create RS256 tokens?
This page is for HS256 if that is what the title and controls show. RS256 needs an asymmetric private key workflow.

Should I use production secrets?
No. Use test secrets here and generate production tokens inside your trusted application or signing service.

Why did token generation fail?
The header or payload may not be valid JSON, or a required secret may be missing.

Should I trust a JWT just because it decodes?
No. A token must be verified and its claims checked by the receiving system.