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Decode a JWT token

Written byPhuoc Nguyen
Created
23 May, 2020
Last updated
13 Oct, 2021
Category
Misc
JavaScript version
decode.js
const decode = (token) =>
decodeURIComponent(
atob(token.split('.')[1].replace('-', '+').replace('_', '/'))
.split('')
.map((c) => `%${('00' + c.charCodeAt(0).toString(16)).slice(-2)}`)
.join('')
);
TypeScript version
decode.ts
const decode = (token: string): string =>
decodeURIComponent(
atob(token.split('.')[1].replace('-', '+').replace('_', '/'))
.split('')
.map((c) => `%${('00' + c.charCodeAt(0).toString(16)).slice(-2)}`)
.join('')
);
Examples
examples.js
decode(`
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.
eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0I
joxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c
`);

// { "sub": "1234567890", "name": "John Doe", "iat": 1516239022 }
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