How To Shrink Windows 10 To Make Space For Linux


This tutorial is part of a larger guide showing how to dual boot Windows 10 and Ubuntu Linux.

Regardless as to whether you wish to dual boot with Ubuntu or any other version of Linux you will need to make space for it and if you only have one hard drive the only way to do that is to reduce the amount of space that Windows is using.

This procedure is very safe as long as you don’t try and shrink any further than the shrink tool suggests.

It is definitely worth checking out this guide for backing up Windows 10 first if you haven’t already seen it. It is better to be safe than sorry.

The tool used for shrinking Windows partitions is “Disk

To start “Disk Management”, right click on the Windows start button in the bottom left
corner of the screen and click on the “Disk Management” option.

A screen will appear listing all the disks available to you
and the partitions on the disk that is selected within the window.

The hard drive is usually disk 0. It is usually easy to spot because it is larger than the other drives and already has a number of partitions on it. As you can see from the image
above there are 4 partitions. The amount of partitions on your hard drive may

For example the screenshot above shows the partitions on my computer which used to run Windows 8 (UEFI) and the screenshot below shows the partitions on my computer which used to run Windows 7 (BIOS).











What you are looking for is the NTFS partition which is both
active and primary. In most cases it is drive C. It is also likely to be the
largest partition on the drive.

NOTE: If your computer does not have an EFI partition and there are 4 partitions on the drive which say primary then you should read this guide before continuing as you cannot have more that 4 primary partitions on a non-EFI drive.

Right click on the partition which contains Windows (as
described above, probably the C drive, NTFS file format, primary and active).

Click on the “shrink volume” option.

When the shrink dialogue box appears it will have the
maximum amount of space available to shrink listed with an up and down arrow to
increase or decrease the amount of space made available to Ubuntu.

Do not make the
number if the “Enter the amount of space to shrink in MB” (box 3) larger than
the “Size of available shrink space in MB” (box 2). This is the equivalent to
ghostbusters crossing the streams.

You can make the amount of space available to Ubuntu smaller
though. The minimum required by Ubuntu is 7 gigabytes which is 7000 megabytes.
In reality you should be looking to give at least 20 gigabytes (20000
megabytes) to Ubuntu for a decent experience and if you have it I would go for
50 gigabytes (50000 megabytes).

Of course if you so wish you can leave the recommended
amounts as they are.

When you have decided on an amount enter it into the box and
click “Shrink”.

When the process has finished you should see that the C
drive has become much smaller (or smaller by the amount you entered in the
shrink dialogue box and that a new unallocated portion of disk space has

You now have space to fit at least one Linux distribution alongside Windows 10.



  1. Hi Gary from enrico, Italy
    I've done the same thing, but with Gparted in the live USB distro (Mint).
    I mean: why don't partiton disk and then install it without exit from Linux Live?
    And i found Gparted easier than Disk management on windows 🙂

  2. Hi Gary, hoping you can help me. I've not been successful so far to install ubuntu on my laptop running w10. Ubuntu installer doesn't recognize windows 10 installed, so I can't (apparently) do the easy install. I've turned off the hibernate option in windows based on something I've read. That didn't appear to work. When I try to create partitions myself to install it, i create the first partition and the rest of my free space becomes unavailable. Another blogger told me not to have too many primary partitions, but I wouldn't know how or why there are too many… Any ideas?

    • Are you using the partitioning tool as part of the Ubuntu installer to create partitions? If you are make sure that you aren't entering all of the disk space when creating the partition and leaving some free space for the swap partition. I don't think this is because of primary partitions being limited to 4 because Windows 10 uses GPT partitioning and this allows for much more than 4 partitions.

  3. i could not install ubuntu on the volume i shrunk out of C drive. The volume was declared as unallocated in disk management. When i tried to install ubuntu on it, it showed that space as unusable and i could not install ubuntu

    • I have seen this happen before and it is because Windows has installed something at the end of the disk leaving hardly any space available when shrinking. Are you running any encryption tools? The chances are that there is a Windows process running which is writing a temporary file at the end of the disk. Stop the windows process, delete the file. The trouble is finding the offending process and file. I don't know of an easy fix.

    • There is no event with ID 259 in app log. There are some events with ID 258.
      I have deleted the pagefile, deactivated system protection and hibernation. I did defragment. i restarted.
      I still cannot shrink at all (I have 75GB free space).
      Is there another thing I can try?

  4. I followed your instructions but either there was a fix or I did something incredible because upon running efibootmgr the boot order was already set correctly! I thought you might like to know that is a possibility now.

  5. The above instructions are clearly incomplete when we are talking about the windows system partition. Windows, maybe on purpose, usually writes information on the end of the system partition, making it impossible to shrink it by the regular way. You'll have to delete previous Windows system images created by the OS to allow returning to a previous Windows state and remove the ability of Windows to use the hard disk as temporary memory, between other things. Only when the final part of the system partition is cleared of any usage, will it be possible to shrink it.

  6. Looks like I'm having a similar problem to a couple of others. Everything is good up until selecting the drive space to install ubuntu. When it asks me where I want to install, it doesn't give me the "install alongside windows 10" option, so I click on "something else." On the next screen, it shows the various drivesan and such, and what I think is the drive space I separated in the c drive, but lists it as unusable,so I can't put ubuntu on it. Any hand available for this?

  7. i could not install ubuntu on the volume i shrunk out of C drive. The volume was declared as unallocated in disk management. When i tried to install ubuntu on it, it showed that space as unusable and i could not install ubuntu

  8. Same here. When I pre-shrink the partitions in windows it doesn't see any operating system installed when running the ubuntu install. When going to the "something else" option to manually choose a partition it is unusable. Everything else up to that point was spot on in the articles though as far as backups and setting up ubuntu installer on jump drive!

  9. Thanks for the guide! I have been following the steps but I got a problem. When I start the installation of Ubuntu 16.04 LTS I get this error:

    "You need at least 8.4 GB disk space to install Ubuntu. This computer has only 8.1 GB."

    This happens because ubuntu just recognize the usb drive and not the partitions of my SSD. A detailed description of the components of the laptop where I'm trying to install Ubuntu is here:

    Hope you guys can help me with this.


  10. I am facing the same problem as my frnd Anmol Kohli. After shrinking the volume is showing unallocated in disk management. When i tried to install ubuntu on it, it showed that space as unusable and and cant proceed.

  11. Has anyone found a solution to the issue of the unallocated space being "unusable"? I have not been able to install Ubuntu due to this issue, despite having followed the steps on this blog, and having nearly identical window to the one at the end of this blog.

  12. I just installed Ubuntu 16.04.1 using the Gary's instructions without any issues. The Ubuntu installer automatically accesses the "unallocated" partition and completes its installation if you choose "Install UBuntu alongside Windows" Option. The part of the instructions that I did not follow is the Macrium backup and boot menu.

  13. Hi,
    I tried to install dual boot (window 10 and Ubuntu 16.04.1). Installion went well.
    I dont use Macrium backup and boot menu.

    I made folloing changes in BIOS.
    The first in Boot order is window boot manager.
    F12 boot menu is enabled.

    Now I could get grub with window and Ubuntu. Alltimes it goes to boot Window, not showing Ubuntu. How can I solve the problem?

    Best regards

  14. please reply my question..I am facing a problem. After shrinking the volume is showing unallocated in disk management. When i tried to install Kali on it, it showed that space as unusable and and cant proceed.

  15. Like so many others, having followed the instructions in this guide I find that Ubuntu cannot install onto the 'unallocated space', and I have no idea how to proceed from here. I assume the author doesn't know either, otherwise he would have proposed a viable solution by now. If only I'd read the comments section before assuming this was the correct process to create space for an Ubuntu installation! Gary, if you read this comment, pls delete this blog so no-one else heads off down this route!

    • Hi, Sorry I'm not ignoring you guys. I just get asked lots of questions every week.

      I will discuss the reasons this could happen this week in a special blog post.

      I have a question for you though…. Do you know if your computer boots via EFI or via a standard BIOS? The answer to this will help me determine the cause of your problem.

      To find out:

      In the search box at the bottom of the screen type "System Information" and when the icon appears at the top click on it.

      Halfway down the right panel there is an item called BIOS mode. If it says UEFI then respond to this comment with yes it is UEFI if not reply saying BIOS or NOT UEFI. Alternatively you can send me a screen shot of your disk management screen via email:

      I think I know what the issue is but I want to be 100% sure

    • BIOS mode is shown as "Legacy" in the system information box. If it helps, the PC originally ran Windows 7 and then (against my better judgement!) I 'upgraded' to Windows 10.

      Many thanks for looking into this – judging by the number of online searches concerning similar issues (none of which so far have worked for me) I suspect installation problems may be a significant cause of people giving up and sticking with Micro$oft.

    • It is as I thought it would be. If you are in legacy mode and you already have 4 primary partitions then you cannot create any more primary partitions. The solution is to take one of the primary partitions, turn it into multiple extended partitions. I will write a guide for doing this.

    • Ok, that's wonderful, thanks.

      I'm hoping (and I'm sure many others will be in the same boat on this) that this can be done in such a way that Windows will not be compromised, as I'm not yet at the stage where I'm ready to commit to ditching it (attractive though that idea sounds).

      Thanks again!

    • I have successfully installed ubantu 16.04 alongside win10 on a reallocated drive partition.I did not use Macron.The only way now that I can select between the 2 is to reboot, go into the bios and alter the boot sequence.Although I can connect to wifi with win10 no problem,ubantu wont recognise anything I try re wifi networking.Thus I cannot download anything to ubantu that you have suggested in your other blogs

  16. While partitioning my F drive which was created from C drive, disk management show error stating no disk space left even though there is 270 GB left. Please suggest how should I create partition for ubuntu installation. If I shall use third party software such as Mini Partition wizard, will it affect my hardware or wil corrupt windows. Awaiting reply at earliest.

  17. Just pointing out a slight exaggeration when explaining why a backup is a good idea… Assuming your PC still has the Microsoft sticker on it, you WILL NOT have to pay again to install your original Windows version. Entering your license key on the download site will get you a brand new installation for free. Cheers!

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