JWT Generator
Create and sign a JWT with a custom header, payload, and secret key — free and processed entirely in your browser.
About JWT Generator
Testing an API that expects a JWT, or just need to see how a token is actually built, means creating one from scratch — assembling the header and payload, then signing it correctly. This tool builds a valid, signed JWT from whatever header and payload you provide.
Edit the header and payload as JSON, choose HS256, HS384, or HS512, and provide your signing secret. Everything runs locally in your browser using the Web Crypto API; your secret key is never sent anywhere.
How to Create a JWT
Step 1
Edit the header and payload
Write your JWT's header and payload as JSON.
Step 2
Enter your secret key
Provide the secret key to sign the token with, and choose your algorithm.
Step 3
Copy your token
Copy the finished, signed JWT.
Frequently Asked Questions
Which signing algorithms are supported?
HS256, HS384, and HS512 — the HMAC-based algorithms, using a shared secret key rather than a public/private key pair.
Can I generate a token signed with RS256 or another asymmetric algorithm?
Not currently — this covers HMAC-based signing (HS256/384/512), which covers the vast majority of everyday JWT testing and development use.
Is my secret key sent anywhere?
No. Signing happens entirely in your browser using the Web Crypto API.
Can I verify a token I already have instead of creating a new one?
Yes — use our JWT Decoder tool to inspect an existing token's header and payload.