This script will delete all but the last 5 versions of a docker image from the local machine (not from the registry)

image-cleanup.sh

#!/bin/bash

IMAGE_NAME=$1
VERSIONS_TO_KEEP=5
TOTAL_VERSIONS=$(docker image ls | grep $IMAGE_NAME | grep -v latest | wc -l)
VERSIONS_TO_DELETE=$((TOTAL_VERSIONS - VERSIONS_TO_KEEP))

if [ $VERSIONS_TO_DELETE -gt 0 ]; then
  echo "Deleting $VERSIONS_TO_DELETE old versions"
  docker image ls | grep $IMAGE_NAME | grep -v latest | tail -n $VERSIONS_TO_DELETE | awk '{print $3}' | xargs docker image rm
else
  echo "No old versions to delete"
fi