JWT Decoder

Decode JSON Web Tokens in your browser, inspect header and payload JSON, and quickly review claims like alg, iss, sub, exp, and scopes.[web:307][web:308][web:317]

Parts detected

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Algorithm (alg)

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Paste your JWT

Token data stays in your browser. Do not paste production secrets or tokens you would not expose in logs.[web:307][web:311][web:317]

Auto decode

Decoded header & payload

Header

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Payload (claims)

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Signature (raw)

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Paste a JWT above to see its decoded header and payload. This tool does not verify signatures or keys; use it for inspection only.[web:308][web:312][web:315]

AD SLOT #2 (IN-CONTENT) — good location for a responsive in‑article AdSense unit near the main decoder content.[web:126][web:141][web:228]

What is a JWT (JSON Web Token)?

A JSON Web Token consists of three Base64URL‑encoded parts separated by dots: header, payload, and signature. It is used to represent claims between parties in a compact, URL‑safe format.[web:307][web:312][web:316]

Why use a JWT decoder?

Debug authentication issues by inspecting claims like exp, iss, aud, scopes, and custom fields.[web:308][web:312][web:313]
Verify that your identity provider or API gateway is issuing tokens with the expected algorithms and metadata.[web:308][web:311][web:317]
Learn how JWTs are structured and how header, payload, and signature pieces work together for integrity and verification.[web:314][web:316][web:320]

Security reminder

Decoding a JWT only reveals its contents and does not prove it is trustworthy. Signature verification with the correct key is required before relying on any claims contained in the token.[web:307][web:311][web:313]

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