How to Check Disk Usage with df and du
Two commands cover disk usage in Linux: df shows free space per filesystem, and du shows how much space files and folders use. df -h prints readable totals for every mounted disk, and du -sh * ranks what is eating your home directory.
Check free disk space with df -h
Run df -h to see each filesystem, its size, how much is used and free, and its mount point. The -h flag turns raw blocks into GB and MB. The mount point column tells you which disk a path lives on.
Show free space for one directory
Pass a path to check the filesystem a folder sits on. This is how you confirm whether /var and /home are on the same disk.
See folder sizes with du -sh
The combo -sh means summarize (one line per argument) in human-readable units. Run it with a glob to rank the contents of your home directory:
Find the biggest folder in a tree
To hunt down what fills a disk, list the largest immediate children, then descend into the largest one and repeat. For a one-shot look at every folder one level deep, use du -h --max-depth=1 and sort.
Free up space
Once you find the culprit, delete old archives, clear package caches, or move the folder elsewhere. Combine with find to spot files larger than 100 MB: find / -size +100M. See df and du for all options.
Keep learning
Related guides: How to Find Files and Directories with the Linux find Command · How to Compress and Extract Files with tar · The Linux ls Command: List Files Like a Pro. Read all tutorials on the Learn Linux blog.