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How to make a bootable macOS USB drive fast, with no special software

By Gabriel · 2026-10-25

Short answer: you do not need any special program to make a bootable macOS USB drive. Download the macOS installer from the App Store and run the createinstallmedia command that comes inside Apple's own installer from Terminal. In the video I do it with OS X El Capitan and rename the flash drive to "123" so the command is easy to type without mistakes.

If you are searching for how to make a bootable macOS USB drive, how to create a macOS installer USB without third-party software or how to use createinstallmedia in Terminal, this guide has the full process. You only need a Mac, a USB flash drive and the macOS installer from Apple. No ISO files and no special apps.

Below I expand my video with a requirements checklist, the command for newer macOS versions (which is shorter than the one shown for El Capitan in the video), how to boot from the USB on Apple silicon and Intel Macs, a troubleshooting table and an FAQ. Apple updates its instructions for every macOS release, so check Apple's official page "Create a bootable installer for macOS" for the exact command for your version.

In this article

What you need
Rename the flash drive to something simple
Download the macOS installer
Open Terminal and become root
Type the createinstallmedia command
If you get an error, check what you typed
Confirm the erase and wait
How to boot a Mac from the bootable USB
Troubleshooting a bootable macOS USB
Safety tips
When is a bootable USB useful?
Frequently asked questions
Watch the video

What you need

A working Apple computer (Mac).
A USB flash drive. Everything on it will be erased, so back it up first.
The macOS installer downloaded from the App Store (El Capitan in the video; the method works for other versions).
Apple's official guide as a reference: Create a bootable installer for macOS.

The advantage of this method is that it is legal and official: no ISO files from unknown sites and no third-party apps.

A Mac that is compatible with the macOS version you want to install. In most cases you must download the installer from a Mac that is compatible with that version.
A USB flash drive. Apple says 32 GB is more than enough for any macOS installer, and 16 GB is enough for most earlier versions.
A backup. The flash drive is erased during the process, so copy anything you need first.
The full macOS installer in the Applications folder, named Install followed by the macOS name.
An internet connection when you later use the installer, because the Mac may need to download firmware and information for your model.

Step 1: Rename the flash drive to something simple

Open Finder, right-click the flash drive (or two-finger tap on the trackpad or Magic Mouse) and choose Rename. I recommend a short name like 123. You will type that name inside the command later, and a simple name avoids typos and spaces that break the path.

Why rename. You will type the name in the Terminal command, so a short name with no spaces avoids typos.
In the video I use 123. Apple's own guide uses MyVolume. Use whichever name you like, but use the same name in the command.
Connect the drive directly to the Mac, not through a hub if you can avoid it.

Step 2: Download the macOS installer

Go to the App Store, find the version of macOS you want and download it. When it finishes, the installer sits in your Applications folder (for example "Install OS X El Capitan"). You do not need to open it.

Where to get it. Apple explains how to download macOS in its support article, and you can use the App Store, a link from Apple or Terminal for some versions.
Do not run the installer. If the installer opens automatically after downloading, quit it.
Check the name and location. It should be an app named Install macOS plus the version name, in the Applications folder.

Step 3: Open Terminal and become root

Click the Spotlight magnifying glass at the top right, type Terminal and press Enter. In the video I type sudo -i, press Enter and enter the Mac's password. You need to see the word root on the command line; if it is not there, the next command will not work. Apple's guide puts sudo in front of the command; if that does not work for you, log in with sudo -i first as shown in the video.

Open Terminal with Spotlight (the magnifying glass) or from the Utilities folder.
Administrator password. When Terminal asks for your password, it does not show any characters as you type. That is normal.
Two ways. In the video I use `sudo -i` to become root first. Apple's current guide puts `sudo` at the start of the command instead.

Step 4: Type the createinstallmedia command

The command has three parts: the path to createinstallmedia inside the installer, the volume of the flash drive, and the path of the application. For El Capitan and a drive named 123 it looks like this:

/Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia --volume /Volumes/123/ --applicationpath /Applications/Install\ OS\ X\ El\ Capitan.app/

Type everything exactly the same, respecting capital letters, slashes and the backslash before every space.
Use the Tab key to autocomplete: pressing Tab twice after /Volumes/ shows every external drive connected, including yours (123).
After --volume goes the flash drive path; after --applicationpath, the installer path.

Newer macOS versions use a shorter command. For example, Apple's guide for macOS Sonoma 14 is `sudo /Applications/Install\ macOS\ Sonoma.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume`.
Older versions such as El Capitan need `--applicationpath` followed by the path of the installer, as shown in the video.
Tab key. Press Tab to autocomplete a path, and press Tab twice after /Volumes/ to list the drives.
Check every slash and space. The backslash before each space is required.

Step 5: If you get an error, check what you typed

If you press Enter and see an error message, it is almost always a typo. That is exactly what happens in the video: I delete the wrong part, fix it, press Enter again and the command works.

"Command not found" usually means the installer is not in the Applications folder, is named differently or the command has a typo.
"Not a valid installer" means the installer may be damaged. Delete it and download it again.
A message about removable volumes. If Terminal asks permission to access files on a removable volume, click OK.

Step 6: Confirm the erase and wait

The command warns that it will erase the flash drive. If you already backed it up, type Y and press Enter. It first erases the disk and then copies the installer. Depending on the computer and the flash drive it can take from about 15 minutes (with a fast drive) up to an hour. When it finishes, the bootable USB is ready to reinstall the system from scratch.

Type Y to confirm that you want to erase the drive, then press Return.
Wait. The process erases the drive and copies the installer. Time depends on the Mac and the drive. In my video it can be from about 15 minutes to an hour.
When it finishes, the flash drive is named after the installer, for example Install macOS Sonoma. Eject it safely.

How to boot a Mac from the bootable USB

Mac with Apple silicon 1. Shut down the Mac and connect the USB drive. 2. Press and hold the power button until startup options appear. 3. Choose the installer and click Continue. Intel Mac 1. Shut down the Mac and connect the USB drive. 2. Turn it on and immediately hold the Option (Alt) key. 3. Release it when you see the bootable volumes, select the installer and press Return. 4. On a Mac with an Apple T2 Security Chip, check that Startup Security Utility allows booting from external media if the drive does not appear.

Troubleshooting a bootable macOS USB

Problem	What to check
The volume is not found	The name in the command must match the drive name exactly.
Permission or "not allowed" message	Allow Terminal to access removable volumes and use sudo with an administrator account.
Erase fails	Use Disk Utility to erase the drive as Mac OS Extended (Journaled), then try again.
The drive does not appear at startup	Reconnect it directly, check the boot steps for your type of Mac and check external boot is allowed on T2 Macs.
Installer says it cannot be used on this Mac	The macOS version may not be compatible with your Mac.

Safety tips

Back up the flash drive and the Mac you plan to erase.
Download macOS only from Apple. Official installers are safer than ISO files from unknown sites.
Type the command carefully. The command erases the drive you name, so check the volume name before you press Enter.
Keep the Mac plugged into power during the process.

When is a bootable USB useful?

You do not need a bootable installer to upgrade or reinstall macOS in most cases. It is useful when the usual methods fail, when a Mac does not start properly, or when you want to install macOS on several computers without downloading the installer every time. For computer repair work, having a bootable USB ready saves a lot of time.

For more Mac and Windows guides, see how to use your iPhone from a Mac remotely with iPhone Mirroring, how to swap a Lenovo motherboard and keep the same components and how to remove viruses, spyware and trojans from a PC.

Frequently asked questions

Do I need to download an ISO file or a program?

No. Everything is done with the official installer from the App Store and the createinstallmedia command that comes inside it, from Terminal.

Why rename the flash drive to 123?

Because the drive name is part of the command (/Volumes/123/). A short name without spaces avoids typing mistakes.

Will it erase what is on my flash drive?

Yes. The process erases everything on the flash drive, so back it up before confirming with Y.

How long does it take?

It depends on the computer and the flash drive: from about 15 minutes with a fast drive up to half an hour or an hour.

What if the command gives an error?

Check that everything is typed exactly right, including the volume name, and that you are root (sudo -i). Fix the mistake and press Enter again.

Which command should I use for newer macOS versions?

Apple's guide lists a shorter command for each version, without --applicationpath. Check Apple's page "Create a bootable installer for macOS" for yours.

How big should the USB drive be?

Apple says 32 GB is more than enough for any macOS installer, and 16 GB is enough for most earlier versions.

Why does Terminal not show my password?

For security, Terminal does not display characters when you type an administrator password. Type it and press Return.

How do I boot from the USB on an Apple silicon Mac?

Shut down, connect the drive, then press and hold the power button until the startup options appear and select the installer.

Can I use the same USB drive again?

Yes. Erase it and run the command again for another version, or format it as usual.

Need help with this?

Call, text or WhatsApp me at 859-878-0554.

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Watch the video

Original video: how to make pendrive bootable NO SPECIAL SOFTWARE REQUIERED

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