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Docker for Mac stores all containers and images in a single disk image

All images and containers are stored in:

~/Library/Containers/com.docker.docker/Data/vms/0/data/Docker.raw

as opposed to Linux which uses the /var/lib/docker directory.

The size of this image can be configured in the Docker for Mac system preferences:

Docker for Mac resources

If you find docker build is erroring with a “No space left on device” error, this is a likely cause. You can free up space in this disk image by running:

docker system prune

There’s more info in the Docker docs on disk utilization.