How to Convert Disk to MBR or GPT in Windows 11

Before You Start: Important Warnings!

Converting a disk between MBR and GPT with the three methods in this guide erases everything on it. Each method deletes the partitions first, and the files cannot be recovered afterwards. Before you convert the disk, copy everything you want to keep to an external drive or cloud storage.

• Back up your data: Copy all important files, and any program installers or settings you need, from the disk you plan to change. Open the backup copy and check that the files open before you continue.
• Close everything: Shut down any apps that might be using the disk. Open files or running programs can block the deletion and cause errors.
• Administrator access: Sign in to Windows as an administrator. Standard accounts cannot change disk layouts.
• Handle BitLocker first: If the disk is encrypted with BitLocker, decrypt it or suspend protection before you change the disk layout. Save the BitLocker recovery key somewhere safe, away from that PC. Layout and boot changes can trigger a recovery key prompt, and without the key the data stays locked. On Windows 11 Pro, search the Start menu for “Manage BitLocker”. On Home, the equivalent feature is Device encryption, under Settings › Privacy & security.
• Don’t target your Windows drive: You cannot delete the system or boot volume of the Windows installation you are running. The three main methods are for data drives, new drives, or a disk you are preparing for a fresh install. Microsoft’s MBR2GPT tool can convert a system disk without erasing it, and the last section of this guide covers it.

Once your backup is safe and BitLocker is dealt with, choose a method.

Option 1Changing Your Disk Using Disk Management

Disk Management is the built-in Windows tool that shows your drives as a graphical map. It suits anyone who prefers clicking to typing. It is included in Home and Pro editions of a currently supported Windows 11 version (24H2 or 25H2).

Step 1Open Disk Management

The quickest way to open Disk Management is through the Run box.

1. Press Win+R on your keyboard. The Run dialog box opens.
2. Type diskmgmt.msc into the box and press Enter or click OK. The Disk Management window opens.

The window lists your volumes in the top half and your physical disks in the bottom half. Each disk has its own row, labeled “Disk 0”, “Disk 1” and so on, with its size and partitions shown as coloured blocks. Work in the bottom half from here on.

Step 2Delete All Existing Partitions

Disk Management offers the conversion only on a disk with no volumes. If the Convert to GPT Disk or Convert to MBR Disk option is greyed out later, a leftover partition is almost always the reason. So delete every volume first.

1. In the bottom part of the Disk Management window, find the disk you want to change. It is labeled something like “Disk 1” or “Disk 2”.
2. Compare the disk number and size with what you know about the drive. Make sure it is the correct disk before you go on.
3. Right-click the first partition (volume) on that disk.
4. Select Delete Volume… from the menu.
5. Click Yes when Windows warns that the data will be lost. The block turns into free space.
6. Repeat for every partition on that disk until the whole disk shows as Unallocated, with a black bar.

If Delete Volume… is greyed out, the volume is a system, boot or page file volume, or the disk holds the Windows you are running. This method cannot be used on that disk.

Step 3Convert the Disk

With the disk fully unallocated, you can convert it. The option sits on the disk’s label box on the left, not on the black unallocated bar.

1. Right-click the disk label on the left side of the disk row. This is the box that says “Disk 1”, the disk size and “Online”.
2. Look at the menu. It offers either Convert to MBR Disk or Convert to GPT Disk, depending on the style the disk uses now. Windows shows only the other style.
3. Click the option for the style you want. Disk Management converts the disk straight away, with no restart.

To confirm, right-click the disk label again and choose Properties, then open the Volumes tab. Partition style should show the new style. The menu should now offer the opposite conversion, which is how you undo the change if needed.

Step 4Create a New Partition

The converted disk is empty, so it cannot hold files until you create a partition on it. Do that now.

1. Right-click the Unallocated space of the converted disk.
2. Select New Simple Volume…. The New Simple Volume Wizard opens.
3. Click Next and follow the wizard. Choose the size of the partition (the default uses all the space), give it a drive letter, and format it with a file system. Use NTFS, the standard for Windows.
4. Click Finish. The disk now shows a healthy volume with your chosen drive letter.

That’s it. The disk now uses the partition style you chose and has a new volume that appears in File Explorer, ready for files.

Option 2Changing Your Disk Using Command Prompt (DiskPart)

DiskPart is a command-line disk tool that runs in Command Prompt. It works the same in Home and Pro editions of a currently supported Windows 11 version (24H2 or 25H2). Once you know the commands it is fast, and it still works when the Disk Management option is greyed out for no clear reason.

Step 1Open Windows Terminal as Administrator

DiskPart needs administrator rights. Open Windows Terminal as an administrator.

1. Click the Start button.
2. Type Windows Terminal. Windows Terminal appears in the search🔍 results.
3. Right-click Windows Terminal in the results.
4. Select Run as administrator.
5. Click Yes if a User Account Control (UAC) window appears. The terminal opens.
6. Make sure the Command Prompt profile is chosen. Windows Terminal may open PowerShell by default on some systems, so check the tab name and switch from the dropdown arrow if needed.

Step 2Start DiskPart

Next, start DiskPart.

1. Type diskpart into the Command Prompt window.
2. Press Enter.

The prompt changes to DISKPART>. This means DiskPart is ready for your commands.

Step 3List Available Disks

Before you change anything, list your disks so you pick the right number. A wrong number here costs you data.

1. Type list disk at the DISKPART> prompt.
2. Press Enter.

DiskPart prints a table of every disk with its number, status and size. A disk that uses GPT has an asterisk (*) in the Gpt column. A blank Gpt column means the disk is MBR. Match the disk by size to what you expect, since a 1TB drive and a 500GB drive are simple to tell apart.

Step 4Select the Disk to Convert

Now select the disk. Every command after this acts on the selected disk.

1. Type select disk <number>, but replace <number> with the actual number of the disk you want to change (for example, select disk 2).
2. Press Enter. DiskPart replies that the disk you chose is now the selected disk.

This is your last chance to confirm that you chose the correct disk. If you are not sure, type the list command again and check the asterisk and the size. All data on this disk is permanently erased in the next steps.

Step 5Clean the Disk

The clean command wipes all partitions and data from the selected disk. A disk has to be empty before DiskPart will convert it.

1. Type clean at the DISKPART> prompt.
2. Press Enter.

DiskPart confirms that it cleaned the disk. The disk now shows as Unallocated in Disk Management, and you can change its style.

Step 6Convert to GPT or MBR

Now tell DiskPart which partition style you want. Pick one of the two commands below, not both.

• To change to GPT, type convert gpt and press Enter.
• OR, to change to MBR, type convert mbr and press Enter.

DiskPart confirms the conversion. To undo it, clean the disk again and run the other command.

Step 7Create a New Partition

The disk has the right style but no partition yet, so create one. You have two choices.

The first is to close DiskPart and use Disk Management (the first method above) to create a new simple volume.

The second is to keep going in DiskPart:

1. Type create partition primary and press Enter to create a partition that uses all the unallocated space.
2. Type format fs=ntfs quick and press Enter to format it quickly with NTFS. The formatting shows a percentage; wait for it to finish.
3. Type assign letter=<X> and press Enter. Replace <X> with the drive letter you want (for example, assign letter=D). Pick a letter that is not already in use.

That’s it. The disk is now converted, formatted and visible in File Explorer. Close the terminal when you are done.

Option 3Changing Your Disk Using PowerShell

PowerShell is the newer command-line shell in Windows. It uses cmdlets (commands with a verb-noun name) instead of DiskPart’s commands. It does the same job and works in Home and Pro editions of a currently supported Windows 11 version (24H2 or 25H2).

Step 1Open Windows Terminal as Administrator

As with Command Prompt, PowerShell needs administrator rights.

1. Click the Start button.
2. Type Windows Terminal. Windows Terminal appears in the search🔍 results.
3. Right-click Windows Terminal in the results.
4. Select Run as administrator.
5. Click Yes if a User Account Control (UAC) window appears.
6. Choose the Windows PowerShell profile from the dropdown menu, or use the default PowerShell tab if that is what opened.

Step 2List Disks

First, find out which disk you are working with.

1. Type Get-Disk at the PowerShell prompt.
2. Press Enter.

PowerShell shows a table of your disks with their numbers, names, sizes, status and partition style (MBR or GPT). Use it to check the current setup before you change anything.

Step 3Select the Disk Number

Find the disk you want to change and note its number.

1. Look at the results from Get-Disk and find the disk you want to change. Check its size and name to be sure it is the right one.
2. Write down its Number.

Step 4Remove Existing Partitions

Next, remove every partition from the disk. As with the other methods, the disk must be empty before you convert it.

1. Type the command shown in the code block below. Replace <DiskNumber> with the actual number of the disk you found in the previous step (for example, Get-Partition -DiskNumber 2 -EA SilentlyContinue | Remove-Partition -confirm:$false).
2. Press Enter.

The command finds all partitions on the disk you specified and removes them without asking for confirmation on each one. If it reports an error about a partition that is in use, close any apps using the disk and run it again.

Step 5Convert the Disk to GPT or MBR

With the disk empty, set the partition style. Use one of the two commands in the code block below, not both.

• To change to GPT, type the GPT command. Replace <DiskNumber> with your disk’s number (for example, Set-Disk -DiskNumber 2 -PartitionStyle GPT). Press Enter.
• OR, to change to MBR, type the MBR command. Replace <DiskNumber> with your disk’s number (for example, Set-Disk -DiskNumber 2 -PartitionStyle MBR). Press Enter.

PowerShell applies the chosen style to the disk, with no restart needed. If you picked the wrong style, run the other command to switch back while the disk is still empty.

Step 6Create a New Partition

Now create a volume so the disk can hold files. You have two choices.

The first is to close PowerShell and use Disk Management (the first method above) to create a new volume.

The second is to continue in PowerShell:

1. To create a partition using all the unallocated space, type New-Partition -DiskNumber <DiskNumber> -UseMaximumSize (replace <DiskNumber> with your disk number).
2. Then, to format it, type Format-Volume -Partition (Get-Partition -DiskNumber <DiskNumber>) -FileSystem NTFS -Confirm:$false.
3. Finally, assign a drive letter with Get-Partition -DiskNumber <DiskNumber> | Set-Partition -NewDriveLetter <X> (replace <X> with the letter you want).

That’s it. The disk is now converted and ready to use. Open File Explorer to confirm that the new drive appears.

Understanding MBR vs. GPT

The partition style decides how a disk stores its partition table and how the computer’s firmware boots from it. That is why you sometimes need to convert between them.

• MBR (Master Boot Record)This is the older standard, used by older PCs and by legacy BIOS boot. It supports disks up to 2TB and a maximum of four primary partitions.
• GPT (GUID Partition Table)This is the modern standard, used by most current computers and required for UEFI boot. It supports far larger disks and many more partitions (usually 128 in Windows). It also keeps a backup copy of the partition table, so it is generally more reliable and flexible.

Most people want their main Windows 11 drive to be GPT, since Windows 11 requires UEFI firmware. Secondary data drives can stay MBR if they need to work with very old systems. For any drive larger than 2TB, GPT is the right choice.

To convert a Windows system disk from MBR to GPT without losing data, use Microsoft’s MBR2GPT tool, mbr2gpt.exe. It works in two stages. Running mbr2gpt /validate checks whether the disk can be converted, and mbr2gpt /convert does the conversion. Run it from Windows Recovery or from the command line. Microsoft’s MBR2GPT documentation on Microsoft Learn lists the exact options and disk requirements.

If you skip this, the PC will not boot. Before you start, restart into the firmware setup screen and note the current settings, especially the boot mode and boot order. A photo taken with your phone works well.

1. Back up your data, and suspend or decrypt BitLocker with the recovery key saved, as described in the requirements above.
2. Run mbr2gpt /validate. If it reports a problem, fix what it names before you go further.
3. When validation passes, run mbr2gpt /convert. The tool converts the disk and keeps your partitions and files.
4. Restart the🔄 PC and open the firmware setup screen. The key to press depends on the manufacturer, so check your PC’s manual.
5. Change the boot mode from BIOS or Legacy to UEFI, then save and exit. Windows should start from the converted disk.

That’s it. Your system disk is now GPT, the firmware boots in UEFI mode, and Windows 11 keeps all its files and settings.

Summary

Disk Management, Command Prompt (DiskPart) and PowerShell all convert a disk between MBR and GPT, and each erases the disk’s data. Back up your data first, check the disk number twice, and then follow the steps for the method you prefer. For a Windows system disk, use MBR2GPT instead, and switch the firmware to UEFI afterwards. When you finish, the disk has the partition style you need and is ready for files.