JSON Web Tokens encode their header and payload as Base64url strings separated by dots. When you need a quick look at what a JWT contains without setting up a full JWT library, simply paste the token or its individual segments here. The decoder handles the Base64url variant used by JWT, revealing the JSON claims including issuer, expiration time, and custom data fields that are essential for debugging authentication flows.
Convert text to Base64 and back — full Unicode, instantly.
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Base64 supports full Unicode text (UTF-8) encoding. Everything runs in your browser — no data is sent to a server.