What is zsh (shell) on Mac?
By Junaid, maker of Taskglass · Last reviewed
The command-line shell that runs inside Terminal windows and scripts.
zsh is the Z shell, macOS's default command-line interpreter. Every Terminal window or tab runs one, and apps and scripts also start shells to run commands. A name starting with a dash (like -zsh) is a login shell. An idle shell uses virtually no resources; high usage comes from what's running in it.
- Category
- Developer tools
- Made by
- Open source (bundled with macOS)
- Safe to quit:
- With care
Shown in Activity Monitor as zsh, -zsh, bash, -bash
Why is zsh (shell) using so much CPU or memory?
- A script or command running in the shell
- Shell startup files (like .zshrc) doing slow work
- Prompt plug-ins checking git status in large folders
What to do
- 1Check the Terminal window it belongs to and stop the running command with Control-C
- 2Close Terminal windows you don't need
- 3Simplify slow shell startup scripts or prompt themes
Safe to quit? With care.
Quitting closes that terminal session and stops whatever was running in it.
Related processes
Part of the Taskglass Process Library