Use jq to decode a JWT

readme.md

Example usage

• Generate fake token with javainuse.com/jwtgenerator.
• Debug the token on JWT.io.

# Export the token for readability
export TOKEN="eyJhbGciOiJIUzI1NiJ9.eyJ1c2VyX2lkIjoiZGJvd2xpbmciLCJleHAiOiIxNzE5NTA4OTI3IiwiZ3JvdXAiOiJkZXZlbG9wZXIifQ.sLMUZtxw-krA5hTAmKFcem-5uP7I35h6ypIfZKUEuXI"

# Use the command directly
jq -R 'split(".") | .[1] | @base64d | fromjson' <<< "$TOKEN"

# or the bash script
./jwt-decode.sh "$TOKEN"

# or the ZSH function
decode-jwt "$TOKEN"

Output:

{
  "user_id": "dbowling",
  "exp": "1719508927",
  "group": "developer"
}

Output should match the JWT.io debug.

decode-jwt.sh

#!/usr/bin/env bash

jq -R 'split(".") | .[1] | @base64d | fromjson' <<< "$1"

decode-jwt.zsh

# Place this function in .zshrc or a location that is sourced from there.
function decode-jwt() {

  jq -R 'split(".") | .[1] | @base64d | fromjson' <<< "$1"

}