How to create a Windows 10 installer USB drive from a Mac

We previously showed you how to create a Windows 10 USB installation media when performing a clean install of Windows 10, but there might be an instance where the only machine you have available is a Mac. We’ll show you to create a bootable USB flash drive with the Windows 10 installer from a Mac. It’s easier than you think, thanks to the built-in Boot Camp Assistant from Apple.

Download Windows 10 Disc Image

First, you need to download the Windows 10 ISO file. Go to the download page and select the proper edition of Windows 10 in the dropdown menu. If you don’t know what K, KN, or Single Language edition stands for, just select Windows 10 in the list.

Create USB installer with Boot Camp Assistant

After downloading the ISO file, you’ll need to use Boot Camp Assistant to move it to a bootable USB drive.

1. Insert a USB flash drive to your Mac. Make sure it’s at least 8GB, which is usually marked on the USB stick. You can also check by right-clicking the USB drive on your desktop and clicking Get Info. Check if the number next to Capacity is at least 8GB. All the files in the drive will be deleted, so make sure there are no important documents inside.
2. Open Boot Camp Assistant. The easiest way to launch it is through Spotlight Search, which you can bring up by pressing Command and Spacebar. Press Enter to launch the app.
3. Check the box for «Create a Windows 7 or later version install disk» and deselect «Install Windows 7 or later version.»

Click Continue to proceed.

Boot Camp Assistant will automatically locate the ISO file from your downloads folder, but make sure it is the right file. Click the «Choose…» button and locate the ISO file. Make sure the destination disk is the USB thumb drive you’ve inserted.

Click Continue. It can take about 20 minutes to format and set up the USB installer on the Mac.

When Boot Camp Assistant is done, the USB drive will be renamed to WININSTALL. Click Quit to close the app and then Eject the USB drive.

That’s it! You now have a bootable USB drive with the Windows 10 installer. You can use it to configure new Windows 10 PCs from scratch. We told you it was easy!

Have you tried creating a Windows 10 installer USB drive from a Mac before? Did you encounter any issues? Let us know your experience in the comments!

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How to Make a Windows 10 USB Using Your Mac — Build a Bootable ISO From Your Mac’s Terminal

Quincy Larson

Most new PCs don’t come with DVD drives anymore. So it can be a pain to install Windows on a new computer.

Luckily, Microsoft makes a tool that you can use to install Windows from a USB storage drive (or «thumbdrive» as they are often called).

But what if you don’t have a second PC for setting up that USB storage drive in the first place?

In this tutorial we’ll show you how you can set this up from a Mac.

Step 1: Download the Windows 10 ISO file

You can download the ISO file straight from Windows. That’s right — everything we’re going to do here is 100% legal and sanctioned by Microsoft.

If you want an English-language version of the latest update of Windows 10, you can download the ISO here.

If you have a relatively new computer, you probably want the 64-bit version. If you’re not sure, go with the 32-bit version to be safe.

If you want a non-English-language version of Windows, or want to get an older update version, download the ISO here instead.

Step 2: Insert your USB storage drive into your Mac

The ISO file is only about 5 gigabytes, but I recommend you use a USB drive with at least 16 gigabytes of space just in case Windows needs more space during the installation process.

I bought a 32 gigabyte USB drive at Walmart for only $3, so this shouldn’t be very expensive.

Stick your USB drive into your Mac. Then open your terminal. You can do this using MacOS Spotlight by pressing both the ⌘ and Space bar at the same time, then typing «terminal» and hitting enter.

Don’t be intimidated by the command line interface. I’m going to tell you exactly which commands to enter.

Step 3: Use the diskutil command to identify which drive your USB is mounted on

Open Mac Spotlight using the ⌘ + space keyboard shortcut. Then type the word «terminal» and select Terminal from the dropdown list.

Paste the following command into your terminal and hit enter:

You will see output like this (note — your Mac’s terminal may be black text on a white background if you haven’t customized it).

Copy the text I point to here. It will probably be something like

Step 4: Format your USB Drive to work with Windows

Next format your USB drive to Windows FAT32 format. This is a format that Windows 10 will recognize.

Note that you should replace the disk2 with the name of the your drive from step 3 if it wasn’t disk2 . (It may be disk3 or disk4 ).

Run this command using the correct disk number for your USB:

diskutil eraseDisk MS-DOS «WIN10» GPT /dev/disk2

Then you’ll see terminal output like this.

This will probably only take about 20 seconds on a newer computer, but may take longer on an older computer.

Note that for some hardware, you may instead need to run this command, which uses the MBR format for partitioning instead of GPT. Come back and try this command if step 7 fails, then redo steps 5, 6, and 7:

Step 5: Use hdiutil to mount the Windows 10 folder and prepare it for transfer.

Now we’re going to prep our downloaded ISO file so we can copy it over to our USB drive.

You will need to check where your downloaded Windows 10 ISO file is and use that. But your file is probably located in your

/Downloads folder with a name of Win10_1903_V1_English_x64.iso .

Step 6: Copy the Windows 10 ISO over to your USB Drive

Update April 2020: One of the files in the Windows 10 ISO – install.wim – is now too large to copy over to a FAT-32 formatted USB drive. So I’ll show you how to copy it over separately.

Thank you to @alexlubbock for coming up with this workaround.

First run this command to copy over everything but that file:

rsync -vha —exclude=sources/install.wim /Volumes/CCCOMA_X64FRE_EN-US_DV9/* /Volumes/WIN10

Then run this command to install Homebrew (if you don’t have it installed on your Mac yet):

/usr/bin/ruby -e «$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)»

Then use Homebrew to install a tool called wimlib with this terminal command:

brew install wimlib

Then go ahead and create the directory that you’re going to write the files into:

Then run this command. Note that this process may take several hours, you may see 0% progress until it finishes. Don’t abort it. It will use wimlib to split the install.wim file into 2 files less than 4 GB each (I use 3.8 GB in the following command), then copy them over to your USB:

wimlib-imagex split /Volumes/CCCOMA_X64FRE_EN-US_DV9/sources/install.wim /Volumes/WIN10/sources/install.swm 3800

Once that’s done, you can eject your USB from your Mac inside Finder. Note that Windows will automatically rejoin these files later when you’re installing.

Step 7: Put your USB into your new PC and start loading Windows

Congratulations — your computer now should boot directly from your USB drive. If it doesn’t, you may need to check your new PC’s BIOS and change the boot order to boot from your USB drive.

Windows will pop up a screen and start the installation process.

Enjoy your new PC, and your newly-installed copy of Windows.

Quincy Larson

The teacher who founded freeCodeCamp.org.

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How to quickly create a macOS bootable USB on Windows 10

Here are the steps to create a macOS Catalina bootable USB media with GPT partition support on Windows 10 to rescue your Mac computer.

It does not matter whether you use macOS or Windows 10. It’s just a matter of time until your device will refuse to start, which could happen for many reasons, including (and not limited to) file corruption, hardware failure, and buggy update. If the unexpected happens with an Apple computer, you can use a macOS bootable USB with the installation media to repair it.

This is one of the main reasons you should consider making a macOS bootable USB when your device is working properly. However, if none of your devices (MacBook, MacBook Air, MacBook Pro, iMac, Mac Pro, or Mac Mini) aren’t working when you need them the most, then you can use a PC to rescue your Apple device. You can use a Windows 10, Windows 8.1, or Windows 7 device to quickly create a USB bootable installation media to reinstall macOS Catalina or Big Sur on your Mac.

In this guide, you’ll learn the steps to create a macOS Catalina bootable USB installation on Windows 10, which you can use to reinstall or upgrade the Apple OS.

Requirements

Before proceeding, you’ll need the following:

• Broken Mac computer running macOS (version 10.12, 11, or later).
• A trial copy of the TransMac software.
• One high-quality USB flash drive with 16GB of storage.
• Copy of macOS (DMG file).

Create macOS bootable USB installation media

To create a bootable USB drive with macOS, use these steps:

Connect the USB flash drive. (If you have any data on the flash drive, remember to make a backup, as everything on it will be erased.)

Right-click the TransMac app and select the Run as administrator option.

Click the Run button. (If you’re using the trial version, wait 15 seconds.)

TransMac on Windows 10

Right-click the USB flash drive, select the Format Disk for Mac option from the left navigation pane.

Format Disk for Mac using GPT partition

Click the Yes button to format the drive on the warning message.

Format warning

Confirm a name for the drive. For example, “macOS bootable USB.”

Click the OK button.

Format USB for macOS with label

Click the Yes button.

Overwrite warning

Click the OK button.

Right-click the USB flash drive and select the Restore with Disk Image option from the left navigation pane.

TransMac Restore with Disk Image option

Click the Yes button to confirm the erase of the USB flash drive data.

Delete warning

Click the browse button on the right.

Select the .dmg file with the macOS installation files.

Select dmg macOS file to create a bootable USB drive

Click the Open button.

Click the OK button.

Click the Yes button.

TransMac creates a macOS USB bootable drive warning.

Once you complete the steps, you can now insert the USB flash drive on your Mac computer to install, reinstall, or upgrade the operating system to the latest macOS version, which can be Sierra, Catalina, Big Sur, or higher.

Create a GPT partition on USB flash drive

If the USB flash drive is not working with TransMac, it could still be a partition problem. In this case, you may need to redo the entire process again. However, this time you should use the following steps to use the Diskpart command-line utility on Windows 10 to create the appropriate GPT partition, and then follow the above instructions.

To create a GPT partition on a removable drive, use these steps:

Open Start.

Search for Command Prompt, right-click the top result, and select the Run as an administrator option.

Type the diskpart command and press Enter.

Enter the list disk command to view all drives connected to your computer and press Enter.

Type the select disk command followed the number assigned for the USB flash drive (for example, select disk 4 ), and press Enter.

Enter the clean command and press Enter.

Type the convert GPT command and press Enter.

Enter the create partition primary command and press Enter to complete the process.

Once you formatted the USB flash drive with a GPT partition, you can use the instructions mentioned above to use TransMac to create a bootable media, but this time skip steps No. 5 through 10 and continue on step 11.

After the process completes, which can take up to an hour, connect the USB flash drive and power on your Mac holding down the Option key, select the USB drive to begin installing macOS.

If you have problems creating the bootable media, you can get a USB flash drive that comes with macOS Sierra, El Capitan, Catalina, etc., on it with the link mentioned below. (I haven’t tried it personally, but it’s worth the try if nothing works.)

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