“I need to create a boot disk for my machine. I am using Windows 8.1, the system was already installed and have no disk(s). I would prefer to do this via a USB/Flash Drive. How do I do this?
From Microsoft Community User

Windows 8.1 is one of the best popular Windows versions except for Windows 10. So If you are a Windows 8.1 user, you may be wondering: how to create a bootable USB drive for Windows 8.1 ISO, and what do I need before starting? You can find all the answers to your questions in this article. Keep on reading.

Part 1. What Do You Need to Prepare Before Windows 8.1 ISO to USB Burn?

If you are a tech newbie and you are not fiddling with Windows very often, you will need to prepare something before starting your work. You will need something as follows:

  • A computer running Windows operating system;
  • A USB drive with at least 4 GB space or larger;
  • And Windows 8.1 ISO file (you can get this ISO file by following the steps in the next parts).
  • Internet connection in your Windows computer (downloading the ISO file and tool may require high speed of internet connection).

Since the materials are ready now, you are good to go. Check the next part.

Part 2: Make Windows 8.1 ISO to USB Manually

Microsoft allows users to download Windows operating system file for free, and users can choose to create bootable media using program provided by Microsoft.

Once you have prepared well, let us cut to the chase and start the process to create a bootable USB drive from Windows 8.1 ISO file.

Step 1: Download Windows 8.1 ISO file

  • 01First of all, click here to open Microsoft software page to download Windows 8.1 Disc Image (ISO file).
  • 02Scroll down until you see Select an edition section, and click the drop-down menu bar to select Windows 8.1, then click Confirm.

    select windows 8.1 edition
  • 03You will need to select a product language, then click choose the language you want in the drop-down menu, then click Confirm.

    choose product language for windows 8.1 iso
  • 04Choose to download 32 bit or 64 bit as you wish. You will need to choose the edition that is supported by your computer hardware.

    choose to download 32 bit or 64 bit
  • 05Then it will download the selected ISO file into your computer. Remember the location where your ISO file is saved.

Step 2: Burn Windows 8.1 ISO to USB drive

After downloading the ISO file, you can start creating the USB drive from Windows ISO file.

  • 01Click to download and install Windows USB/DVD Download Tool.

    windows usb dvd download tool to burn windowws 8.1  to usb
  • 02Launch Windows USB/DVD Download Tool in your computer, and then you will be prompted to import your ISO file. Browse to the location and import the Windows 8.1 ISO file.
  • 03Choose ‘USB device’ after clicking Next, and you will be prompted to choose your USB drive.

    choose usb device to burn windows 8.1 iso
  • 04Insert your USB flash drive into your computer, then select it.

    Note that creating bootable USB drive will erase all the data in this USB drive, so make sure to back up the important data in your USB drive before this.

  • 05Click Begin Copying. If it pops up to confirm erasing data, confirm it and start.

    begin copying win 8.1 to usb
  • 06The ISO file will be writing to the USB drive. Wait for several minutes until it is competed.

After completing, the whole process is done and you have created a bootable USB drive from Windows 8.1 ISO file.

This process is a little bit complicated and may take some more time. If you want to make it easy and fast, try the next method.

Part 3: Download Windows 8.1 ISO and Create Bootable USB Automatically

The other effective way to convert Windows 8.1 ISO to USB, is to do it via a professional ISO burner. With ISO burner, it helps you download and burn the ISO file as easily as possible, it saves your time and patience to struggle with those long process, and it prevents you from worrying about making any mistakes.

The ISO burner we recommend is PassFab for ISO, which is one of the best Windows ISO burners out there.

  • It supports burning ISO for Windows 10, Windows 8.1, Windows 8, and Windows 7;
  • It supports GPT and MBR partition types;
  • It supports burning ISO to USB of various brands, such as SanDisk, Kingston and Corsair;
  • Last but not least, it is very easy to use, and you can finish all the process with just 4 clicks!

Can’t wait to try it out? Now let’s go directly to the part on how to burn Windows 8.1 ISO to USB via PassFab for ISO.

  • 01Download and install PassFab for ISO in your computer. It’s a small size of program and you can download and install it very fast.
  • 02Launch the program and you will see the user interface as well as the instructions.
  • 03Choose and download Windows 8.1 ISO image or click ‘Import’ and go to the location to import the Windows 8.1 ISO file. select windows 8.1 iso in passfab for iso
  • 04Plug your USB drive into your computer, and choose your USB flash drive in the ‘Create a Bootable USB’ section. Choose partition type and system file, and click Burn. select usb in passfab for iso
  • 05The program will start burning ISO file into your USB drive. burn iso successfully in passfab for iso

After finishing, close the program and unplug your USB drive. And voila! This is your Windows 8.1 bootable USB drive.

Part 4: FAQs About Windows 8.1 ISO to USB

Q1: Is an ISO image bootable?

Well it depends. The ISO image itself isn’t bootable unless it has been burnt. If you want to know your ISO file is bootable or not, you can try third-party software and it will tell you whether your ISO file is bootable.

Q2: Can I just copy Windows ISO to USB?

Copying and pasting your ISO file to USB won’t make it bootable and you cannot boot your computer from USB after that. You will need to burn ISO image to USB using program like PassFab for ISO.

Q3: How do I download Windows 8.1 to a flash drive?

You can directly download Windows 8.1 ISO to a flash drive from Microsoft, but this won’t make it a bootable flash drive, which doesn’t make any sense. You can try Windows USB/DVD Download Tool or PassFab for ISO to burn Windows 8.1 and make it a bootable media.

Bottom Line

There you go. This article outlines detailed instructions to burn Windows 8.1 ISO to USB, step by step. You can do it manually using the Windows USB/DVD Download Tool, or you can try a top Windows ISO burner like PassFab for ISO if you prefer to make it less time-consuming and complex.