How to Create an ISO Image in Windows and Make a Bootable USB Drive
Vladislav Sham
Creating and using disk images has become an essential part of everyday data management. It makes it easy to create bootable media for installing operating systems, transfer programs, or store backups. In this guide, we’ll explain what a disk image is, what it’s used for, how to create one, and how to write a disk image to a drive.
What Is a Disk Image?
A disk image is a file that completely preserves the contents of a physical storage device in its original state. This includes both user data—like files and folders—and service information that controls the device, such as partition tables, boot records, and more.
An ISO image can be seen as an exact copy of everything on the storage device, ensuring high compatibility with different operating systems and software.
Types of Disk Images
Disk images come in different types, each with its own purpose and features. The most popular formats are:
- ISO. This is the most popular and widely supported format for optical media (CD/DVD). An ISO image contains all the data and service structures needed to reproduce the original disc. It’s the standard for creating operating system and software installation packages. ISO is well supported by most operating systems and can be written to physical media like CD/DVD or USB drives.
- BIN/CUE. The BIN/CUE format consists of two files: the BIN file (the data) and the CUE file (which describes the BIN image’s structure). It’s often used for making copies of audio discs or multi-layered data, such as games.
- DMG. The DMG format is used on macOS. It’s a container that holds data and can be mounted on a Mac. This is the main format for distributing applications on macOS, often through the App Store or direct downloads from websites.
In addition to ISO and BIN/CUE, there are other, less common image formats such as:
- NRG.
- UIF.
- CCD.
These formats often need to be converted to ISO for use with other operating systems or programs.
What Are Disk Images Used For?
Disk images serve a variety of useful purposes for everyday users:
- An ISO image lets you create an exact copy of a disk’s contents, which can be used for archiving or backups. This is especially important for making long-term archives of operating systems, applications, or other critical data.
- Many programs and operating systems are distributed as ISO images. This makes installation easier, since you don’t need a physical disk. Just download the image, write it to a drive (like a USB stick), and install.
- ISO images are used to create bootable media. For example, when installing an operating system (Windows, Linux) from a USB flash drive or DVD. All you need to do is write the ISO image to the drive and set your BIOS to boot from it.
- ISO images let you create a virtual disk by mounting the image with programs like Daemon Tools or built-in OS tools. This allows you to work with the contents of the ISO without having to burn it to a physical disk.
How to Create a Disk Image
There are many third-party utilities that let you create an ISO image from files, folders, or even the entire contents of a physical disk.
AnyBurn
AnyBurn is a free program for creating, burning, and managing ISO images. It supports creating images from both files and physical disks (CD/DVD).
Once installed, simply open the program and choose “Create image file from files/folders” or “Create image file from disc”. Then, add the files you want or select the physical disk and choose where to save the image. When the process is complete, you’ll have a disk image ready for further use.
ISO Workshop
ISO Workshop is a simple yet functional program for working with images. It supports creating, extracting, and burning ISO images. It works much like AnyBurn: install — select a disk — save the image.
PowerISO
PowerISO is a powerful tool for working with images and virtual drives. It supports creating, editing, converting ISO images, and many other features. To create a disk image, go to the “Tools” menu, select “Create Image,” then choose your file or disk source and save the image where you want.
How to Write a Disk Image to a USB Drive
Writing an ISO image to a USB stick is most often used for creating bootable media, such as for installing an operating system.
Rufus is a popular free program for writing ISO images to USB drives. It makes it easy to create bootable media and supports a wide range of ISO formats.
How to Use Rufus:
- Download and install Rufus from the official website.
- Plug your USB flash drive into your computer.
- Open Rufus. In the “Device” field, select your flash drive.
- In the “Boot selection” field, click “Select” and choose your ISO image file.
- Under “Partition scheme,” pick MBR (for older systems) or GPT (for modern systems with UEFI).
- For “File system,” leave it set to FAT32.
- Click Start. Rufus will warn you that all data on the flash drive will be erased. Confirm to continue.
Wait for the process to finish. After that, your flash drive will be ready to use as a bootable device.
Important notes:
- Before writing an ISO image to a flash drive or disk, make sure the image size doesn’t exceed your device’s capacity. For example, to write a Windows installation ISO, you’ll need a flash drive with at least 8 GB of space.
- Before writing to your device, make sure the ISO image isn’t corrupted. Some programs (including Rufus) let you check data integrity during the writing process.
- Depending on the size of the ISO and the speed of your device—whether it’s a USB flash drive or an optical drive—the writing process can take anywhere from a few minutes to an hour. Make sure not to interrupt the process.