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$status:last deploy2026-07-25

← /tools / jwt

JWT tool

Decode, encode, and attack JSON Web Tokens. All operations happen in your browser via the jose library — nothing is transmitted to any server.

Runs entirely in your browser — nothing is uploaded and no network request fires on use.

Load existing token

Paste a token to decode it into the editable fields below. Flip any claim (e.g. admin: false → true), then re-sign with a key you control. The signature is not verified on load.

Signing

Header

Custom header claims

No custom header claims.

Values parsed as JSON when possible; otherwise treated as strings. alg / typ are owned by the fields above.

Payload

Custom claims

No custom claims yet.

Values parsed as JSON when possible; otherwise treated as strings.

Preview

{
  "alg": "HS256",
  "typ": "JWT"
}
{}