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JWT decoder

Decode a JSON Web Token and show its header and payload. Tokens are decoded on your device only — never upload a real token to an untrusted site.

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Workspace: 1. Add files2. Ready3. Working4. Done — download

How this workspace works
  1. Paste a JSON Web Token.
  2. Read its decoded header and payload on your device.
  3. Check the claims (such as expiry) before trusting the token.

JWT Decoder

Tokens are decoded on your device only — never paste a real production token into an untrusted site.

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How to use JWT decoder

  1. Paste a JSON Web Token.
  2. Read its decoded header and payload on your device.
  3. Check the claims (such as expiry) before trusting the token.

A good use for this

Inspecting a token during development to see what it actually contains.

Limits

Decoding only reads the token — it does not verify its signature, so a decoded token is not proven genuine. Never paste a real production token into any untrusted site; this tool decodes on your device only.

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