Rufus is a free Windows utility for formatting USB drives and turning operating-system images into bootable media. It prepares drives for Windows or Linux installation, live recovery environments, DOS tools and other utilities that need to run before an installed operating system starts. Its controls connect the source image with the partition layout and boot method required by the destination computer.
Writing an ISO image with Rufus
A bootable ISO contains more than a file to store on a flash drive. Rufus processes the image and prepares the USB’s filesystem and boot components so the computer can start from it. This makes the same utility useful for a Windows installer, a Linux live environment or a disk-maintenance image, while the software inside the selected image determines what runs after boot.
For hybrid ISO images, Rufus offers two writing approaches. ISO mode extracts the image’s files onto the prepared drive, leaving content accessible for additions or changes where the image permits them. DD mode writes the image as a block copy and preserves its supplied layout. The latter can be useful for an image designed around that layout, but it can also leave partitions that Windows cannot read as ordinary storage.
Rufus prepares a drive for one bootable image at a time. It repartitions and reformats the selected device, removing its existing partitions and their contents; it does not maintain a menu of multiple ISO files on the same USB.
BIOS, UEFI and DOS boot media
The Partition scheme and Target system controls determine how the output matches the destination machine’s firmware. With Windows installation images, MBR and the BIOS or UEFI-CSM target create media for BIOS-style booting, while GPT targets UEFI.
Rufus also supports UEFI booting from NTFS through UEFI:NTFS, which provides the filesystem driver needed to access the NTFS content during startup. This allows bootable media to carry individual files larger than FAT32 can hold, such as a large Windows installation file.
DOS boot media provides an environment for compatible firmware flashing tools or low-level utilities. Rufus can select a DOS keyboard layout according to the Windows system’s locale, so the resulting command environment can match the keyboard in use.
Windows setup customizations
Rufus can adjust supported Windows installation media through its Windows User Experience options. These include bypassing selected setup checks such as TPM and Secure Boot requirements, and restoring local-account setup for applicable Windows images when the account-creation stage has no network connection. The choices available depend on the selected image.
An optional Quality of Life setting applies a group of Windows changes, including removal of OneDrive, Outlook and Teams, disabling Copilot, and adjustments to Start-menu and taskbar defaults.
Windows To Go drives
With a compatible Windows image, Rufus can create a Windows To Go drive that runs Windows from USB. This output differs from installation media: Rufus applies the Windows image stored inside the ISO to the external drive, rather than just placing setup files there. Some ISOs contain image data that cannot be processed for Windows To Go, so the option is not available for every Windows ISO.
VHD drive images and Non bootable mode
Rufus can save a selected physical bootable drive as a VHD image through its advanced drive properties. The saved image provides a source for restoring that drive’s contents to the same device or another one later.
When a flash drive is needed for ordinary file transfers again, its Non bootable mode reformats it into a regular storage volume. This removes extra boot partitions, including a UEFI:NTFS partition, and lets Windows recognize the drive’s full capacity again. It creates a fresh storage layout rather than recovering files erased during an earlier write.
