An ubuntu live usb gives you a portable, working copy of Ubuntu that runs on its own without touching the computer’s internal drive. You can install Ubuntu on a new machine, try the desktop before committing, fix a system that won’t boot, or use Ubuntu temporarily on a borrowed laptop. This guide walks through the full process of building one from an existing Ubuntu installation.
What You Need Before Creating an Ubuntu Live USB
Three things have to be ready before you begin. The USB drive will be wiped, so move anything off it first.
| Requirement | Specification |
|---|---|
| USB flash drive | 6GB minimum capacity |
| Existing Ubuntu installation | Ubuntu Desktop 18.04 or later |
| Ubuntu ISO file | Downloaded from the official Ubuntu website |
The ISO file is the disk image of Ubuntu that gets written to your drive. If you’ve never worked with Linux files before, the way Ubuntu organises storage and paths is worth a quick read — this overview of how Ubuntu manages background processes covers some of that ground.
Launching Startup Disk Creator
Ubuntu ships with a built-in tool called Startup Disk Creator. You don’t need to install anything. It handles the entire ISO-to-USB write process from one window.
To open it:
- Plug your USB stick into the computer. If Ubuntu asks what to do with it, pick Do nothing.
- On Ubuntu 18.04 and later, click the icon in the bottom-left corner to open Show Applications.
- On older versions, use the top-left icon to open the Dash.
- Type Startup Disk Creator into the search field.
- Click the application result to launch it.
The tool opens in a small window with two fields — one for the source image, one for the target drive.
Selecting the ISO File and USB Device
When the tool opens, it scans your Downloads folder for ISO files and checks for connected USB drives. In most cases it will already have your Ubuntu ISO listed under Source disc image and your USB under Disk to use.
If either field is wrong:
- Use the Other button to point it to your ISO file manually
- Pick the correct USB device from the list if you have more than one connected
Once both are right, click Make Startup Disk to begin. Ubuntu’s share of Linux web server deployments sits at 13.7%, which is part of why the Startup Disk Creator workflow has stayed consistent across so many releases — the tool is used heavily.
Confirming the USB Device Before Writing
Before the write begins, Startup Disk Creator shows a confirmation prompt. This step is here because the process is destructive — every existing file on the drive will be erased.
Read the prompt carefully, especially if multiple USB drives are plugged in. Once you confirm, a progress bar appears and writing begins. The process usually finishes in a few minutes on a modern machine, though older USB 2.0 drives can take ten minutes or more.
What You Can Do With Your Ubuntu Live USB
Once the write finishes, the drive is ready to boot. Here’s what it lets you do:
| Use case | How it works |
|---|---|
| Install Ubuntu | Boot from the USB and run the installer |
| Try Ubuntu without installing | Run the live session — your existing system stays untouched |
| Repair a broken system | Use the pre-installed recovery tools on the live USB |
| Boot Ubuntu on any compatible machine | Use a borrowed or public computer temporarily |
The live session writes nothing to your internal drive unless you choose to install. Anything you do during the session — files you create, apps you install — disappears when you reboot, unless you set up a persistent USB instead. People who plan to use Ubuntu seriously after this often want to learn how to set up Ubuntu on a Chromebook or move to a permanent install.
Booting From the Ubuntu Live USB
The USB is bootable as soon as Startup Disk Creator finishes. To use it, restart the target computer with the stick plugged in. You’ll need to tell the computer to boot from USB instead of its internal drive.
Most machines respond to one of these keys, pressed during startup:
- F12 — common on Dell, Lenovo, and Acer
- F2 — common on ASUS and Toshiba
- Esc — common on HP
- F10 — used by some HP and other models
Watch the screen during boot — many BIOS splash screens show the right key briefly. If your machine has Secure Boot enabled and won’t pick up the USB, you may need to disable it in BIOS settings.
Creating a Live USB Without an Existing Ubuntu System
This guide assumes you’re already on Ubuntu. If you’re on Windows or macOS, the process uses different tools — Rufus or balenaEtcher are the usual choices on Windows, and balenaEtcher works on macOS too. Ubuntu’s official documentation covers both. The end result is the same: a USB drive that boots into Ubuntu on any compatible computer.
For users who already work with multiple Linux distributions, tools like Popsicle let you write to several USB drives at once, which matters when deploying Ubuntu to a fleet of machines. APT-based distributions including Ubuntu account for roughly 54% of all Linux installations, so having a reliable live USB workflow is something most Linux users end up needing.
FAQs
How big does my USB drive need to be?
6GB is the minimum for a standard Ubuntu live USB. 8GB or larger is recommended if you plan to add persistence — a feature that saves files and settings across reboots. Smaller drives won’t fit the full ISO image.
Will creating an Ubuntu live USB erase my files?
It erases everything on the USB drive, not your computer. Startup Disk Creator overwrites the entire stick during the process. Back up any files on the USB before starting. Your computer’s internal drive stays untouched.
Can I use the same Ubuntu live USB on different computers?
Yes. The live USB works on any compatible machine, regardless of where it was created. You only need to set the target computer to boot from USB. Hardware drivers load automatically during the live session.
Why isn’t my computer booting from the USB?
Two common causes: the boot order in BIOS lists the internal drive first, or Secure Boot is blocking the USB. Press F12, F2, or Esc during startup to open the boot menu, or disable Secure Boot in BIOS settings.
Can I save files on the Ubuntu live USB?
Not by default. Standard live sessions reset on every reboot. To save files and settings, create a persistent live USB instead — this requires a larger drive and a tool like mkusb or Rufus with persistence enabled during creation.
