If you run a lot of containers that require persistent volumes, Docker will create those localized volumes on your system in the background as the container is initializing.

Now, it is simple to run the docker system prune command to automatically wipe your Docker host, but what if you wanted to dive into your setup and to view the docker disk space usage on your system Thankfully, Docker has a built in solution that will allow you to view details on Docker disk space usage.

The output will summarize the different images, containers, local volumes, and build caches on your system and display the quantity of those items, many of those items are in use, how much size those items are taking, and how much space you will reclaim when you remove them.

Then there is the rest of us who prefer a more detailed output.

Docker provides an easy way to view our Docker disk space usage.

Information will be presented in four main categories, images space use, containers space use, local volumes space use, and build cache usage, as seen below.

Docker container images are made from various different layers and if these layers are identical, they can be shared across multiple container images in an effort to save space on your system.

The shared size amount will show how much of a particular container image is being shared with another container.

This section outlines the container ID on your system, the image that the container is running, the command being ran in the container, how many local volumes are attached to the container, and the amount of space that the container is taking up on your system.

Alpine linux is one of the more popular, lightweight base images that are used to create docker containers.

Keep in mind that local volumes are volumes that are within Docker that are created when you start a container that requires them, or when you create them by using the docker volume create command.

Docker disk usage will also increase because when you remove containers, the volumes that are automatically created with the container will remain on the system.

This section does not include volumes that are bound to folders on the host machine.

This section will display the cache ID, type, how much space it is using on your Docker host, when the cache was created and when it was last used.

Similar to the image space use section, the build case usage section outlines which image layers are shared across containers vs.

If you use dockerfiles to build a lot of containers then your docker disk usage could increase because of the space required for build caches.

With this information you can easily pick and choose which items you can delete that you dont need and leave items on your system that you may choose to use later.

More information about the commands in this article can be found in Dockers official documentation.

Docker For Mac Disk Usage