JWT Builder
Build unsigned JWT header.payload from JSON.
Sensitive data: Anything you enter is processed in your browser only. It is never uploaded or logged on a server.
Reference Guide
Security tool — all processing runs locally in your browser. No data is sent to a server.
Operation: jwt-build
Paste input, click Run, and copy the result. For two-input tools, fill both fields before running.
Example Input
{"alg":"HS256","typ":"JWT"}Example Secondary Input
{"sub":"demo","name":"DevPipe"}A sample loads automatically when you open this tool. Use Load Sample to reset it.