nickcernis/docker-cleanup.md

docker kill $(docker ps -q) to kill all running containers
docker rm $(docker ps -a -q) to delete all stopped containers.
docker rmi $(docker images -q) to delete all images.

For fish, remove the $:

docker kill (docker ps -q) to kill all running containers
docker rm (docker ps -a -q) to delete all stopped containers.
docker rmi (docker images -q) to delete all images.