To dual boot Windows 10 and Kali Linux, back up your files, shrink your Windows partition to free up space, write the Kali installer ISO to a USB drive, boot from that USB, and choose Guided – use the largest continuous free space during installation. Kali installs the GRUB boot menu, which lets you pick Windows or Kali each time you start the PC.
This guide walks through each stage in order, with the settings that trip people up most often: BitLocker, Fast Startup, Secure Boot, and partitioning.
What you’ll need
- A Windows 10 PC with at least 20 GB of free disk space for Kali (more if you plan to install many tools; 50 GB or more is comfortable).
- A USB flash drive of 8 GB or larger. Everything on it will be erased.
- The Kali Linux Installer image for your PC’s architecture (usually 64-bit, amd64) from the official Kali download page.
- A USB writing tool such as Rufus or balenaEtcher.
- A full backup of anything important. Partitioning is safe when done carefully, but a mistake can wipe data.
Step 1: Prepare Windows 10
- Back up your files to an external drive or cloud storage.
- Save your BitLocker recovery key if your drive is encrypted. Changing boot settings can trigger a recovery prompt. Check in Control Panel > BitLocker Drive Encryption; you can also suspend protection there until setup is done.
- Turn off Fast Startup. Go to Control Panel > Power Options > Choose what the power buttons do > Change settings that are currently unavailable, and uncheck Turn on fast startup. This stops Windows from leaving the disk in a half-hibernated state that Linux can’t safely touch.
- Check your boot mode. Press Windows + R, type
msinfo32, and look at BIOS Mode. Most PCs show UEFI. Kali should be installed in the same mode as Windows.
Step 2: Shrink the Windows partition
- Right-click the Start button and choose Disk Management.
- Right-click your Windows partition (usually C:) and select Shrink Volume.
- Enter the amount of space to free up in MB. For example, 51200 MB gives Kali 50 GB.
- Click Shrink. You’ll see a block of Unallocated space. Leave it unformatted; the Kali installer will use it.
If Windows won’t shrink as much as you want, unmovable system files are in the way. Temporarily turning off hibernation or the page file can help, but the simplest fix is to accept a smaller amount.
Step 3: Create a bootable Kali USB
- Plug in your USB drive.
- Open Rufus, select the USB drive under Device, and click Select to choose the Kali ISO.
- Set Partition scheme to GPT for UEFI systems (or MBR for legacy BIOS systems).
- Click Start. If Rufus asks about ISO or DD image mode, choose DD Image, which Kali’s documentation recommends for its images.
- Wait for it to finish, then safely eject the drive.
Step 4: Boot from the USB
- Restart the PC with the USB plugged in.
- Open the boot menu with the key your PC uses (often F12, F11, F9, or Esc) and choose the USB drive. You can also go to Settings > Update & Security > Recovery > Advanced startup > Restart now, then Use a device.
- If the USB won’t boot, Secure Boot may be blocking it. Turn Secure Boot off in your UEFI settings and try again.
- At the Kali boot menu, choose Graphical install.
Step 5: Install Kali Linux alongside Windows
- Pick your language, location, and keyboard layout.
- Let the installer configure the network, then enter a hostname (any name for the computer) and leave the domain blank unless you need one.
- Create your user account and password. Kali uses a standard user with sudo rights rather than logging in as root.
- At Partition disks, choose Guided – use the largest continuous free space. This uses only the unallocated space you created and leaves Windows untouched.
- Choose All files in one partition (the simplest option), review the summary, and confirm with Finish partitioning and write changes to disk, then Yes.
- Select the desktop environment and tool collections. The defaults (Xfce and the top 10 tools) are a good start; you can add more later.
- When asked about the GRUB boot loader, choose Yes and select your main drive (not the USB).
- When installation finishes, remove the USB and restart.
Step 6: Choose your OS at startup
After restarting you’ll see the GRUB menu. Pick Kali GNU/Linux to start Kali, or Windows Boot Manager to start Windows. If nothing is selected, the top entry starts after a few seconds.
If the PC goes straight into Windows without showing GRUB, open your UEFI settings and move the Kali (or “debian”) boot entry above Windows Boot Manager in the boot order.
Common problems and fixes
| Problem | Fix |
|---|---|
| Windows doesn’t appear in GRUB | Boot Kali and run sudo os-prober, then sudo update-grub. If os-prober is disabled, set GRUB_DISABLE_OS_PROBER=false in /etc/default/grub first. |
| BitLocker recovery screen in Windows | Enter the recovery key you saved, then resume BitLocker protection. |
| Installer can’t see the hard drive | Change the SATA mode from RAID/Intel RST to AHCI in UEFI settings. Make sure Windows can still boot afterward. |
| Clock is wrong in Windows after using Kali | In Kali, run timedatectl set-local-rtc 1 so both systems use local time. |
| No Wi-Fi in Kali | Use Ethernet temporarily and install the driver for your wireless chipset. |
Alternatives to dual booting
If you only need Kali occasionally, you might not need a dual boot. Kali runs in a virtual machine such as VirtualBox or Hyper-V, in Windows Subsystem for Linux (WSL), or live from a USB drive. These are safer for your Windows install but give less direct hardware access, which matters for some wireless testing tools.
Related: How to dual boot Windows 11.
Related: How to install Linux on Windows 10.
Frequently asked questions
Is it safe to dual boot Windows 10 and Kali Linux?
Yes, if you back up first and install Kali only into the unallocated space. The main risk is choosing the wrong disk or partition during setup.
How much space does Kali Linux need?
Kali’s minimum is about 20 GB. More space gives room for extra tools, updates, and your files.
Do I have to turn off Secure Boot?
Not always. Kali can start with Secure Boot on some PCs, but if the USB or installed system won’t start, turning it off is the usual fix.
How do I remove Kali later?
Set Windows Boot Manager first in your UEFI boot order, delete the Kali partitions in Disk Management, extend C: into the free space, and remove the Kali boot entry.
Should I use Kali as my everyday OS?
Kali is built for security testing. For everyday Linux use, a general-purpose distribution such as Ubuntu or Debian is a better fit.
Kermit Matthews is a freelance writer based in Philadelphia, Pennsylvania with more than a decade of experience writing technology guides. He has a Bachelor’s and Master’s degree in Computer Science and has spent much of his professional career in IT management.
He specializes in writing content about iPhones, Android devices, Microsoft Office, and many other popular applications and devices.