Many Windows users know that creating a bootable USB on a Windows machine is an extremely easy process. All you need is a cheap 8GB+ USB drive and the official utility called Media Creation Tool (you can download it on the official website). When it comes to creating a bootable USB on a Mac, Apple’s laptops are not that friendly and easy. Sure, you won’t need nothing to reinstall macOS in case of a software emergency, but this process requires an Internet connection. Also, you can’t downgrade macOS without a bootable USB. This also applies to bulk and offline installation. The fastest way to reinstall the operating system is to use an offline bootable USB on Mac.
What Do You Need to Create a Bootable USB on MacOS?
First, you need an external drive with 16 GB of data. You can’t use an 8 GB flash drive since this amount is not enough to store all the necessary files. Also, make sure you back up all the important data because your computer will wipe the drive when you create a bootable USB on Mac. Second, you need a working Mac to download macOS files and save them on a drive. Yes, you can do this on a Windows machine using some wacky third-party apps, but in this article, we will focus on how to create a bootable USB on Mac using Mac only. Third… There’s no third. You don’t need any additional software to install macOS from USB. The built-in Therminal is the only app you need. And yes, the Internet connection is required.
How to Make a Bootable USB on Mac?
Creating a bootable USB on Mac is a two-step process. First, you need to download a specific macOS version from the Mac App Store. Second, write all the necessary files to a USB drive using the special createinstallationmedia command. That’s it. That is how you create a bootable USB on Mac that in turn allows you to install macOS from USB.
How to Download macOS on Mac?
Before you start, make sure you try to download a supported macOS version. If your Mac does not support the latest release or an older version of macOS, Mac App Store will show you an error. For your convenience, here’s the link to the official Apple’s support page where you can find all the information about macOS support from OS X Snow Leopard up to the latest macOS Catalina.
Now, open the Mac App Store using Launchpad, the menu bar or the Spotlight and search for the macOS you want to install. For example, Catalina.
If for some reason you can’t locate the macOS version you need, use the following links to quickly jump to the specific Mac App Store pages.
Hit the download button and wait for the system to get all the necessary files. For your information: downloading the currently installed release will open the system’s settings and initiate download using the built-in update mechanism. That is how it supposed to work. Just wait for the process to finish.
After the process is finished, you will find a new app in the Applications folder called Install macOS. It will launch automatically but you don’t need it at all, so simply close it and move to the next part of this guide that describes how to create a bootable USB on Mac.
Create Bootable USB on Mac
Now it is time to create a bootable USB with macOS and later use it to install macOS from a USB drive. Before we go, make sure you know the Administrator password otherwise, macOS won’t allow you to run the necessary command in the Terminal. Also, prepare your USB drive. This is where you need to plug it into your computer.
Tip: if you use MacBook 12, MacBook Pro 2016 or newer or MacBook Air 2018 and newer, you probably wonder how to use a regular USB-A drive with your Type-C only computer. You can either buy USB hub for MacBook or get a USB-C thumb drive. One of the best we can highly recommend is from Samsung called Samsung Duo Plus USB 3.1 Flash Drive. It is a very affordable USB drive that works both with USB-A and USB-C. It is available in 32, 64, 128 or 256 GB flavors and the price is extremely good. There’s another solid option (even cheaper) called SanDisk Ultra Dual Drive Go. It will work very well with your Mac and serve as a perfect solution for installing macOS from USB.
Let us now move to the process of making a bootable USB on Mac. Before running the command, make sure your Mac “sees” your USB drive and it is properly formatted as Mac OS Extended. Needless to say that if the drive formatted as FAT32 or NTFS, you need to format it using the appropriate file system. When formatting, create a simple name for your drive. For example, call it simply a USB. This will save you time and avoid making a mistake when typing a command to create a bootable USB on Mac in the Terminal.
- Open Terminal from the Launchpad, Spotlight or the Applications folder.
- Enter the following command:
Tip: In this command, we assume you named your drive as USB. If you use another name, replace the USB at the end of the command with the correct name of your drive. Be accurate otherwise, the Terminal will return an error.
For macOS Catalina use:
sudo /Applications/Install macOS Catalina.app/Contents/Resources/createinstallmedia --volume /Volumes/USB
- If you install an older operating system, use the following commands. macOS Mojave:
sudo /Applications/Install macOS Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/USB
macOS High Sierra:
sudo /Applications/Install macOS High Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/USB
- Hit Return. If the command is correct, Terminal will ask your Administrator password. Do note that symbols do not appear on the screen when you type in your password, so don’t think Terminal is stuck or your keyboard does not work.
- On the next step, Terminal asks you whether you want to erase the Volume on the drive. Hit Y on your keyboard and then Return.
- Sit back and wait for Terminal to finish copying all the necessary files. In the end, Terminal should tell you that the copying process is complete. Now it is safe to remove your bootable USB drive and use it to install macOS from a USB.
That’s it. As you can see, creating a bootable USB on Mac is a relatively easy and hassle-free process that requires you to know only one large Terminal command. Good thing is that whenever you need to create a bootable USB on Mac, our handy guide is always ready to provide all the necessary information.