Base64 & JWT Decoder

Name: Base64 & JWT Decoder
Author: Daniel Cáceres López

Encode/decode Base64 and decode JWT tokens.

READY

base64__jwt_decoder.tool

READY

Mode

Base64JWT decoder

EncodeDecode

Input

Output

SGVsbG8sIFdvcmxkIQ==

// HOW IT WORKS

Base64 encodes binary data as text; a JWT is three Base64url parts (header.payload.signature). The tool encodes/decodes Base64 and decodes JWT claims — all locally.

Example

'hi' → Base64 'aGk='. A JWT's middle part decodes to its claims, e.g. { "sub": "123", "exp": 1750000000 }.

Notes

Decoding a JWT does NOT verify it — the signature still needs the secret/public key to be trusted.
JWT uses Base64url (- and _ instead of + and /, no padding), a variant of standard Base64.