jwt decode shell script

jwtdecode.sh

#!/bin/sh

# Decode JWT token
# Usage: echo <jwt_token> | jwtdecode
# requires jq and coreutils

while read -r input;do
  echo "$input" | cut -d . -f 1,2 | tr '.' '\n' | \
    while read -r str;do
      echo "$str" | basenc -d --base64url | jq .
    done
  done

AFAIK the base64 variant used in JWT is base64url which is supported by coreutils basenc(1). So you can replace echo "$str"==== | fold -w 4 | sed '$ d' | tr -d '\n' | base64 --decode | jq with echo "$sr" | basenc -d --base64url | jq.

Nice, thank you!