Creating a bootable Linux USB drive means writing a Linux installation image to a flash drive, then starting a computer from it. With a suitable live image, you can test Linux before installing it, check hardware support or keep recovery tools available.
The process works from Windows, macOS and Linux. The main precaution is choosing the correct USB drive: writing an image erases its contents. Copying the ISO file onto an ordinary USB drive does not produce the same result.
What You Need Before Starting
Prepare a working computer, an internet connection and a USB flash drive large enough for your chosen distribution’s image. An 8GB drive works for many desktop images, including Ubuntu’s documented requirements, but check the download instructions rather than assuming every image will fit. A 16GB drive provides more room if the image requires it.
Back up anything stored on the USB drive before proceeding. Disconnect other removable storage, especially backup drives, to reduce the chance of selecting the wrong device. Check the target’s manufacturer name and capacity in the writing application, not just its drive letter.
You do not normally need to format the USB drive first when using an image writer such as Etcher. The application replaces its existing contents during writing. Formatting it beforehand mostly adds another opportunity to select the wrong disk.
Download the Correct Linux Image
Download the installation image from your chosen distribution’s official download page. If you have not decided which distribution to use, start with our guide to choosing a Linux distribution rather than downloading several images at random.
For a typical Intel or AMD computer with a 64-bit processor, look for an image labeled x86_64, x64 or amd64. The amd64 label also applies to compatible Intel processors. ARM computers require an appropriate ARM image, and matching the processor architecture alone does not guarantee hardware support.
Choose a desktop live image if you want to try Linux before installation. A network installer or server image may start an installer instead of providing a desktop.
Verify the Download
Compare the downloaded image’s SHA-256 checksum with the value published by the distribution. A mismatch means you should stop and download the image again.
A checksum checks file integrity; authenticating the published checksum file with the distribution’s signing key provides a separate authenticity check. The Ubuntu download verification procedure covers both checks. Verification is worth doing before spending time diagnosing a USB drive written from a damaged download.
Write the USB Drive with Etcher
BalenaEtcher provides a graphical method for supported Windows, macOS and Linux systems. Download the application through its official project pages and choose the build for the computer you are using to create the USB.
That computer does not have to match the installation target. You can, for example, use an Apple Silicon Mac to write an x86_64 Linux image intended for an Intel or AMD PC. The Etcher application must suit the Mac; the Linux image must suit the destination computer.
- Connect the USB drive. Close any files or folders open from it.
- Open Etcher and choose Flash from file. Select the completed Linux image download.
- Choose Select target. Confirm the USB drive’s name and capacity. Stop if you cannot identify it confidently.
- Click Flash! Approve the administrator permission request if prompted.
- Wait for writing and validation to finish. Do not unplug the drive while either stage is running. Eject it before removal if your operating system still shows it as connected.
The Etcher user documentation covers the application’s workflow. Its validation checks the written data; it does not replace verifying the original download or prove that the target computer supports the image.
Linux Alternative: GNOME Disks
If your Linux desktop already includes Disks, you can use it instead of installing another writer. Open Disks, select the USB device in the sidebar, then open the drive menu and choose Restore Disk Image…. Select the ISO, click Start Restoring… and confirm the destination before authorizing the operation.
Despite the word “restore,” this writes the installation image onto the USB drive. Wait until it finishes, then eject the device. The Ubuntu bootable USB instructions document this method and other platform options. They also distinguish creating media on a Mac from installing Linux on Apple Silicon, which requires a hardware-appropriate installation route.
Windows Alternative: Rufus
Rufus provides another Windows option. Select the USB under Device, use SELECT to choose the ISO, review the settings and click START. Follow your distribution’s instructions if it requires particular settings.
If Rufus offers ISO mode and DD mode, do not assume one is universally correct. ISO mode extracts files, while DD mode writes the image directly. Follow the distribution’s recommendation where one exists; otherwise, start with the offered default. The Rufus FAQ on image modes and boot behavior covers these differences. Wait for Rufus to report completion before removing the drive.
Start the Computer from the USB
Insert the finished USB drive into the computer you want to test, then restart it. Open the temporary boot menu using the button documented by the computer or motherboard manufacturer. Select the USB drive rather than the internal storage device.
On a UEFI computer, choose the UEFI USB entry when available, particularly if you intend to install alongside an existing UEFI operating system. The Debian installation manual’s firmware and boot selection guidance covers boot device selection and firmware considerations.
If the image provides a live desktop, choose its “Try” or live-session option. An installer-only image will behave differently. Reaching an installation menu confirms that the computer has started from the USB; you do not need to begin installation to test that.
If the USB Does Not Work
The Computer Starts Its Existing Operating System
Try the temporary boot menu again and confirm that you selected the USB device. Connect it directly rather than through a hub, and try another port. If it never appears, check the computer’s USB boot settings and the image’s hardware requirements.
Writing or Validation Fails
Keep the ISO on the computer’s internal storage, reconnect the USB and retry. If failures continue, use another port or another flash drive. Repeated validation errors deserve attention; do not treat a partly written drive as ready to use.
You See a Format Prompt or Security Error
After writing, Windows may offer to format a partition it cannot read. Cancel that prompt: formatting can damage the installation media.
For a Secure Boot error, check the distribution’s current installation notes and confirm that you downloaded a current supported image. Do not disable security settings automatically just because a generic troubleshooting post suggests it.
Test Linux Before Installing
In a live desktop, test Wi-Fi, sound, the keyboard, touchpad and external displays. Our Linux hardware compatibility checklist gives you a more systematic test plan. Starting a live session does not itself install Linux, but tools inside it can still modify internal drives if you tell them to.
Do not assume a standard live USB saves installed applications or settings between restarts. Persistence requires a supported setup; an installation USB is not automatically a portable workstation.
Once testing is complete, follow the Linux installation guide for the installation stage. Back up the destination computer before changing its storage layout.
If you intend to keep Windows, review the separate Linux and Windows dual boot guide before proceeding. Creating the USB is preparation, not permission to click “erase disk.”