To remove all unused containers, networks, images (both dangling and unused) that are older than 30 days, use the following command:
`docker system prune -a --filter "until=720h"`
- `-a`: remove all unused images, not just dangling ones
- `—-filter`: the filtering flag, for example: `—-filter ”until=720h”` which says „all elements that are older than 30days.
---
Instead of using `system` you could use one of the following, to scope the objects you want to delete:
- image
- containers
- volumes
- networks
##### System Prune Example output
```bash
docker system prune -a --volumes
WARNING! This will remove:
- all stopped containers
- all networks not used by at least one container
- all anonymous volumes not used by at least one container
- all images without at least one container associated to them
- all build cache
Are you sure you want to continue? [y/N] y
Deleted Containers:
0998aa37185a1a7036b0e12cf1ac1b6442dcfa30a5c9650a42ed5010046f195b
73958bfb884fa81fa4cc6baf61055667e940ea2357b4036acbbe25a60f442a4d
Deleted Networks:
my-network-a
my-network-b
Deleted Volumes:
named-vol
Deleted Images:
untagged: my-curl:latest
deleted: sha256:7d88582121f2a29031d92017754d62a0d1a215c97e8f0106c586546e7404447d
deleted: sha256:dd14a93d83593d4024152f85d7c63f76aaa4e73e228377ba1d130ef5149f4d8b
untagged: alpine:3.3
deleted: sha256:695f3d04125db3266d4ab7bbb3c6b23aa4293923e762aa2562c54f49a28f009f
untagged: alpine:latest
deleted: sha256:ee4603260daafe1a8c2f3b78fd760922918ab2441cbb2853ed5c439e59c52f96
deleted: sha256:9007f5987db353ec398a223bc5a135c5a9601798ba20a1abba537ea2f8ac765f
deleted: sha256:71fa90c8f04769c9721459d5aa0936db640b92c8c91c9b589b54abd412d120ab
deleted: sha256:bb1c3357b3c30ece26e6604aea7d2ec0ace4166ff34c3616701279c22444c0f3
untagged: my-jq:latest
deleted: sha256:6e66d724542af9bc4c4abf4a909791d7260b6d0110d8e220708b09e4ee1322e1
deleted: sha256:07b3fa89d4b17009eb3988dfc592c7d30ab3ba52d2007832dffcf6d40e3eda7f
deleted: sha256:3a88a5c81eb5c283e72db2dbc6d65cbfd8e80b6c89bb6e714cfaaa0eed99c548
Total reclaimed space: 13.5 MB
```
### See also
1. [[What is Dangling Image?]]
2. [[How filters in Docker command work?]]
### Reference
1. [Prune usused Docker objects on Docker website](https://docs.docker.com/engine/manage-resources/pruning/)