JWT Decoder
Decode the header and payload of a JWT (without verifying the signature). The token never leaves your browser.
Frequently Asked Questions
What is a JWT?
A JSON Web Token is a compact format for securely transferring data between services; it has three parts — header, payload and signature — separated by dots.
Is the content of a JWT confidential?
No. The header and payload are just Base64URL and anyone can read them; the signature only prevents tampering, not reading. Do not put sensitive data in a JWT.
Does this tool verify the signature?
No; it only decodes and displays the header and payload. The token never leaves your browser.