How to free up disk space used by Docker

Over time, Docker accumulates old images, stopped containers and unused volumes that take up disk space. Here is how to clean up.

1. See how much Docker uses

docker system df

2. Quick, safe cleanup

Remove stopped containers, unused networks and dangling images:

docker system prune

3. More aggressive cleanup

Also includes unused images (not just dangling ones):

docker system prune -a

4. Be careful with volumes

Volumes hold your data. Only delete them if you are sure:

docker volume prune

Check first which volumes are orphaned with docker volume ls, so you do not lose application data.

5. Automate

Add a weekly cleanup to cron:

0 4 * * 0 docker system prune -af

When the disk is too small

If you still run out of space, you need a bigger disk. With hourly billing you can move to a plan with more storage quickly, or move data to a Backup Box.