How it works
Paste any JWT (JSON Web Token) string into the decoder. It instantly splits the token into header, payload, and signature sections, decodes the Base64 content, and displays the claims — including expiry (exp), issued-at (iat), and subject (sub).
Why use this tool?
Developers debugging authentication issues use this free JWT decoder to inspect token contents without needing jwt.io. Works fully offline — your token never leaves your browser.