Is it possible to use ls in Unix to list the total size of a sub-directory and all its contents?

By itself, ls does not provide a command-line option to display the total size (sum of all files) of a subdirectory. The ls utility lists filenames and their attributes, but it doesn’t output a single cumulative size.

To get the total size of a directory (including all its files and subfolders), use du (disk usage) instead. For a human-readable summary:

du -sh /path/to/directory

• -s: Summarize the total size of the directory rather than listing each file.
• -h: Show sizes in a “human-readable” format (e.g., KB, MB, GB).

If you run:

du -sh /path/to/directory/*

you get individual human-readable sizes for every item inside directory, as well as the total for each subfolder.

Why Not ls?

• ls -l lists files and their sizes but shows per-file information rather than a total.
• ls -s displays disk blocks used by each file. Again, this doesn’t aggregate the values into a single total.

Hence, du is the standard tool whenever you need the total size of a directory on Unix-like systems.

Further Learning

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