Decode JWT segments and verify.. JWT Debugger is a free online tool from the ToolsRift Developer Tools collection. It runs entirely in your browser — nothing to install, no signup, and your data never leaves your device.
Paste a JWT and the tool splits it on the dots, Base64URL-decodes the header and payload to readable JSON, and shows the raw signature segment.
Decoding happens entirely in your browser with no network requests, but avoid pasting live production tokens into any online tool as a precaution.
Verification needs the signing secret or public key. This debugger decodes the header and payload; use a signing tool to verify or issue tokens.
iat is the issued-at time and exp is the expiry, both Unix timestamps. A token is expired once the current time passes exp.