Rufus 4.15 is a free Windows utility under the GPL-3.0-or-later license that formats USB drives, flash cards and virtual drives, and writes ISO files or disk images to bootable media. It handles BIOS and UEFI layouts, FreeDOS or MS-DOS drives, Windows To Go, and Windows 11 installers for PCs without TPM or Secure Boot. The program is only 1.9 MB, and this build was released on June 30, 2026.
The problem: an ISO file and no way to boot it
An operating system image is useless on a PC until it sits on a drive the firmware can start from. Rufus handles that step. It formats USB sticks, flash cards and virtual drives to FAT, FAT32, NTFS, UDF, exFAT, ReFS, ext2 or ext3.
It also writes the boot structures, so the same stick can start a machine in either BIOS or UEFI mode.
From Windows 11 media to FreeDOS sticks
Rufus builds drives from bootable ISOs, including Windows and Linux images, and from disk images, compressed ones too. DOS drives can use FreeDOS or MS-DOS. UEFI bootable NTFS is supported, which matters for large Windows install files.
Two options stand out for Windows users: installation drives for Windows 11 on PCs without TPM or Secure Boot, and Windows To Go drives.
What to check before you install
The developer says no installation is required and that the program is portable and Secure Boot compatible.
Writing to a drive erases what is on it, so confirm the target device first. Choose the right partition scheme for the target PC, since BIOS and UEFI machines expect different setups.
What's new in 4.15
Version 4.15 adds RISC-V 64 support to UEFI:NTFS and fixes a crash during boot with UEFI:NTFS on Snapdragon X ARM64 platforms. It also fixes the silent Windows installation option failing at 75% in most cases.
Rufus pros and cons
Pros
- Free under GPL-3.0-or-later
- Only 1.9 MB and needs no installation
- Supports BIOS and UEFI boot, including UEFI bootable NTFS
- Handles ISOs and compressed disk images
- Can build Windows 11 media for PCs without TPM or Secure Boot
Cons
- The interface cannot be previewed on this page
- Writing to a drive overwrites its contents
- Windows only
Is Rufus safe?
Rufus is written by pbatard and released under GPL-3.0-or-later, so its source code is open for anyone to read. Version 4.15 patches the ezxml parser, closing an unrestricted XML entity expansion and an integer overflow. It also fixes a UEFI:NTFS boot crash on Snapdragon X ARM64 machines and an infinite loop with Windows ISOs that contain multiple WIMs.
How to install Rufus
- Press the download button to get the official file.
- Run the installer you saved and confirm the Windows security prompt if the publisher matches.
- Follow the setup steps, then start Rufus from the Start menu.
