How to Run a Shell Script (.sh) on macOS

To run a shell script on macOS, open Terminal, go to the folder containing the .sh file, and run it with its interpreter. For example, bash hello.sh runs a Bash script without changing its permissions. If you want to launch it as a command, make it executable with chmod +x hello.sh, then run ./hello.sh. These methods work on current macOS releases.

Check the script before running it

A shell script is a plain-text file containing commands. Those commands run with the permissions of your user account, so a script can edit or delete files, install software, or send data over a network. Read a script you received before running it, especially if it asks for an administrator password or uses sudo. Only run scripts from sources you trust; changing a file’s permissions does not make its contents safe.

Apple describes shell scripts as text files that contain UNIX commands and explains how a shebang selects the shell that runs the script. See Apple’s Terminal guide to shell scripts.

Run a .sh script with Bash

This is the simplest way to run a Bash script. You do not need to add execute permission first.

1. Create or locate the script. A shell script can be written in any plain-text editor. For a quick test, open TextEdit, choose Format > Make Plain Text, and enter these two lines:

#!/bin/bash
echo "Hello from macOS"

Save the file as hello.sh. In the save dialog, check that the name ends in .sh and that TextEdit has not added .txt. The first line is the shebang: it identifies Bash as the interpreter when the script is launched directly. The second line prints a short message.

2. Open Terminal and go to the file’s folder. Press Command-Space, type Terminal, and press Return. If you saved the file in Downloads, enter:

cd ~/Downloads

Press Return after each command. You can type ls to list files and confirm that hello.sh is there. Change Downloads to the folder you actually used. If a folder or file name contains spaces, put the path in quotation marks, such as cd "$HOME/My Scripts".

3. Run the script with Bash. Enter the script name after bash:

bash hello.sh

Terminal should display Hello from macOS. If the script uses Zsh syntax instead of Bash, run zsh hello.sh. The shell that opens interactively in Terminal is usually Zsh, but that does not mean every script should be run with Zsh; use the interpreter the script was written for. A script’s shebang often indicates that interpreter.

Run the script as an executable

You can also launch a script directly by its path. This is useful when you want to run it like a small command. Apple’s Terminal instructions for making a file executable use chmod for this step.

1. Grant execute permission. In the same Terminal window and folder, run:

chmod +x hello.sh

This adds execute permission to this file. It is a one-time change unless permissions are later reset. Avoid using broader permission settings than needed; chmod +x is sufficient for a personal script you own.

2. Launch it from the current folder. Type:

./hello.sh

The ./ tells the shell to run the file in the current directory. Without it, the shell generally searches folders listed in PATH rather than the current folder. If you are elsewhere, either use cd to return to the script’s folder or enter its full path, for example ~/Downloads/hello.sh.

Common errors and fixes

• “Permission denied” after using ./hello.sh: confirm the filename, then run chmod +x hello.sh. Or use bash hello.sh if it is a Bash script and you do not need direct execution.
• “No such file or directory”: confirm the folder with pwd, list its contents with ls, and check the spelling and capitalization. Make sure the file is not actually named hello.sh.txt.
• “Command not found” inside the script: the script may rely on a utility that is missing or not on PATH. Check the script’s documentation before installing anything.
• “Bad interpreter” or an error mentioning ^M: the first line may point to an unavailable interpreter, or the file may use Windows-style line endings. Check the shebang and save the file with Unix (LF) line endings.

Which method should you use?

Use bash hello.sh for a quick run when you know it is a Bash script. Use chmod +x hello.sh followed by ./hello.sh when you want to launch it directly and let its shebang choose the interpreter. Neither method installs missing dependencies, fixes incompatible commands, or verifies whether the script is trustworthy.