If you need to install Windows or Linux and you don’t have access to a CD/DVD drive, a bootable USB drive is the solution. You can boot to the USB drive, using it to run the OS setup program, just like a CD or DVD.

We have collected some links to free programs that allow you to easily setup a USB drive to install Windows or Linux on a computer.

NOTE: If you have problems getting the BIOS on your computer to let you boot from a USB drive, see our article about booting from a USB drive even if your BIOS won’t let you.

Windows USB/DVD Download Tool

Editor’s Note: if you want to create a bootable Windows install USB, this is the tool you should choose.

The Windows USB/DVD Download Tool is an official, freeware tool from Microsoft that allows you to install Windows 7 and Windows 8 and Windows 10 without having to first run an existing operating system on your computer. You can change the boot order of the drives in your computer’s BIOS so the Windows installation on your USB drive runs automatically when you turn on your computer. Please see the documentation for your computer for information about how to access BIOS and change the boot order of drives.

Rufus

RELATED: How to Create a Bootable Linux USB Flash Drive, the Easy Way

Rufus is a small, portable program that allows you to create bootable USB drives for Windows and Linux. It also allows you to check the USB device for bad blocks, using up to four passes. Rufus runs in both 32-bit and 64-bit versions of Windows XP, Windows Vista, Windows 7, and Windows 8. You can create bootable USB drives for the listed versions of Windows, as well as almost all popular Linux distributions, such as Ubuntu, Kubuntu, Fedora, and OpenSUSE. It’s our current preferred way to create Linux Live CDs and USB drives.

Rufus is very easy to use and the program looks like the default format window shown in Windows when you format a hard disk partition, USB drive, or other external drive.

In addition to Windows and Linux systems, you can also use Rufus to put utilities on USB drives, such as Parted Magic, Ultimate Boot CD, and BartPE.

UNetbootin

UNetbootin is a free program for both Windows, Linux, and Mac OS X that allows you to create bootable Live USB drives for Ubuntu, Fedora, and other Linux distributions instead of burning a CD. It runs on both Windows and Linux. Either use UNetbootin to download one of the many Linux distributions it supports or provide the location of your own Linux ISO file.

NOTE: The resulting USB drive is only bootable on PCs, not Macs. In addition, UNetbootin isn’t as reliable as it once was—we now recommend one of the other tools mentioned here, like Rufus.

Ubuntu Startup Disk Creator

The Ubuntu Startup Disk Creator allows you to convert a USB flash drive or SD card into a drive from which you can run your Ubuntu system. You don’t have to dedicate the whole drive to the Ubuntu system. You can store other files in the remaining space.

The program also allows you to create a drive for Debian, or any other Debian-based OS for which you have a CD or .iso image.

Universal USB Installer

Universal USB Installer is a program that allows you to choose from several Linux distributions to install on a USB flash drive. Select the Linux distribution, provide a location for the appropriate ISO file, select your USB flash drive, and click Create.

NOTE: The USB flash drive must be formatted as a Fat16, Fat32, or NTFS drive.

WiNToBootic

WiNToBootic is another free tool that allows you to create a bootable USB flash drive for installing Windows 7 or Windows 8. It supports an ISO file, a DVD, or a folder as the boot disk source. It’s a standalone tool that doesn’t require installation and it operates very fast.

Note: this tool doesn’t appear to be developed anymore.

Windows Bootable Image (WBI) Creator

Update: this tool doesn’t seem to exist anymore.

WBI Creator is a free program that allows you to create a bootable ISO image from Windows XP, Vista, and Windows 7 setup files. It’s a portable tool that’s easy to use. Simply tell the tool where the Windows setup files are and select a target folder for the new ISO file that will get created. Then, you can use one of the other tools mentioned in this article to setup a bootable USB flash drive or CD/DVD for use in setting up a Windows system.

WinToFlash

Update: we’ve been told by our readers that this application has a lot of adware so we’re removing the link.

WinToFlash is a free, portable tool that allows you to create a bootable USB flash drive from a Windows XP, Vista, Windows 7,  Server 2003, or Server 2008 installation CD or DVD. It will also transfer a Windows pre-install environments (WinPE), which are handy for troubleshooting and repairs, to a USB flash drive. You can even use WinToFlash to create a MSDOS bootable USB drive.

XBoot

Update: this tool hasn’t been updated in a very long time.

XBoot is a free utility for creating multiboot USB flash drives or ISO image files. This allows you to combine multiple ISO files (Linux, utilities, and antivirus rescue CDs) onto one USB drive or ISO file, allowing you to create a handy utility drive. Simply drag and drop the ISO files onto the XBoot window and click Create ISO or Create USB.

NOTE: XBoot requires .NET Framework 4.0 (Standalone installer or Web installer) to be installed on your system to run.

If there are any other free tools you’ve found useful for creating bootable USB flash drives, let us know.