Fixing the Zsh Error: 'Command Not Found: Mongo' - Troubleshooting Guide

When working with the MongoDB command-line interface, you might encounter the error "Command not found: mongo" while using the Zsh shell. It usually happens when the Mongo command is not recognized in the system's PATH variable or when MongoDB is not installed properly. This troubleshooting guide will help you fix this issue step by step and provide answers to some frequently asked questions.

Table of Contents

  1. Verify MongoDB Installation
  2. Check the PATH Variable
  3. Add MongoDB to the PATH
  4. FAQs

Verify MongoDB Installation

The first step is to ensure MongoDB is installed on your system. You can do this by following the official MongoDB installation guide for your operating system. After installation, run the following command to check the MongoDB version:

mongod --version

If MongoDB is installed correctly, you should see the version information.

Check the PATH Variable

The next step is to check if the MongoDB binary is in your system's PATH variable. Run the following command to display the contents of the PATH variable:

echo $PATH

Look for the MongoDB binary directory in the output. It should look similar to the following:


If you do not see the MongoDB binary directory in the PATH variable, you need to add it manually.

Add MongoDB to the PATH

To add the MongoDB binary directory to the PATH variable, follow these steps:

  1. Open the Zsh configuration file (.zshrc) in your favorite text editor:
nano ~/.zshrc
  1. Add the following line at the end of the file, replacing /path/to/mongodb/bin with the correct path to your MongoDB binary directory:
export PATH=$PATH:/path/to/mongodb/bin

Save the changes and close the text editor.

Reload the Zsh configuration file to apply the changes:

source ~/.zshrc
  1. Test the Mongo command again:
mongo --version

If everything is configured correctly, you should now see the MongoDB version information.


1. How do I find the path to the MongoDB binary directory?

The MongoDB binary directory location depends on your operating system and installation method. Some common locations are:

  • macOS: /usr/local/mongodb/bin
  • Ubuntu: /usr/bin/mongodb/bin
  • Windows: C:\Program Files\MongoDB\Server\4.2\bin

If you cannot find the binary directory, try searching for it using the find command:

find / -name "mongo" 2>/dev/null

2. How do I uninstall MongoDB?

To uninstall MongoDB, follow the official MongoDB uninstallation guide for your operating system.

3. How do I switch from Zsh to another shell?

To switch from Zsh to another shell, such as Bash, run the following command:

chsh -s /bin/bash

Replace /bin/bash with the path to the desired shell.

4. Can I use MongoDB with other shells like Bash or Fish?

Yes, MongoDB can be used with other shells like Bash or Fish. You just need to make sure the MongoDB binary directory is added to the PATH variable for the respective shell.

5. How do I update MongoDB to the latest version?

To update MongoDB to the latest version, follow the official MongoDB upgrade guide for your operating system.

Great! You’ve successfully signed up.

Welcome back! You've successfully signed in.

You've successfully subscribed to

Success! Check your email for magic link to sign-in.

Success! Your billing info has been updated.

Your billing was not updated.