How to Convert MBR to GPT in Windows 10 without Data Loss?
Sometimes, you might need to convert MBR to GPT Windows 10. Here we will teach you how to convert MBR and GPT using Command Line, Disk Management and a professional converter (which can convert disk to MBR or GPT without data loss and without reinstalling Windows in Windows 11, 10, 8, 7).
About MBR and GPT
Prior to learning how to convert MBR and GPT disk in Windows 10, let’s have a basic understanding of what is MBR disk and what is GPT disk.
▶ MBR (short for Master Boot Record) allows for a maximum partition size of 2TBs with 4 primary partitions or 3 primary partitions and 1 extended partition. To create over 4 partitions on an MBR disk, you should create (a maximum of) 3 primary partitions and then 1 extended partition that will allow you to create multiple sub-partitions (logical drives).
▶ GPT (short for GUID Partition Table) theoretically doesn’t have any limits on the partition number and the disk size. GPT system disk can only be booted from a UEFI (United Extensive Firmware Interface) enabled system. Only users, whose computer's motherboard supports UEFI, can take advantage of GPT to create an unlimited amount of partitions and make full use of the larger hard disk. But GPT structure can’t be used on removable media (USB sticks, CDs, DVDs etc.).
Why convert MBR to GPT in Windows 10?
Users often ask whether should they use MBR or GPT structure in their Windows 10 PCs. MBR structures can only support disks up to 2TBs in size, which means if you have a drive larger than 2TBs, the surpassing space will show as unallocated that you cannot access and use. Therefore, in order to take full advantage of the big hard disk, you have to convert MBR to GPT in Windows 10. Or if you want to upgrade your Windows 10 PC to Windows 11, you have to select GPT because Windows 11 only boots in UEFI mode.
However, you should note that Windows XP 32-bit, Windows 2003 32-bit, Windows 2000, and Windows NT4 operating systems can’t support GPT disks. When using these systems GPT disks will show "GPT Protective" partitions, and you won’t be able to access the data on the disk until you convert it from GPT to MBR.
As with everything, there are pros and cons to using GPT or MBR partition structures. The majority of today’s users will convert between the structures depending on the present situation and their hardware requirements.
Convert MBR to GPT in Windows 10 via Windows built-in tools (data loss)
To convert MBR to GPT or GPT to MBR in Windows 11/10/8/7, you can first make use of its native tools: Windows Disk Management and DiskPart.exe.
Method 1. Convert MBR to GPT via Windows 10 Disk Management
Windows 10 Disk Management is a built-in tool that allows you to create, delete, format, extend and shrink partitions, and convert disk to GPT/ MBR structures. To use Disk Management, you need to open it by right-clicking on This PC -> Manage -> Disk Management. Next, right-click on the disk you want to convert. In the pop-up menu, you will find the "Convert to GPT disk" or "Convert to MBR disk" option unavailable.
That’s because Disk Managemen is only able to convert between GPT and MBR when there are no partitions on the disk. Therefore, you must first delete all the partitions on the aim disk before conversion. Moreover, the solution only works when you are converting a non-system disk because you cannot delete the system partition within Windows.
Method 2. Convert MBR to GPT in Windows 10 via Command Line
DiskPart is another Windows built-in tool. Same as Disk Management, DiskPart only allows you to convert a disk when there are no partitions on the disk. On the other hand, it is more functional than Disk Management, allowing you to convert both system disk and non-system disk to MBR or GPT. Because you can access the DiskPart command-line in WinPE mode and then delete the system drive before conversion.
To convert a data disk with partitions on, take the following steps:
Step 1. Click on the "Start Menu" and input "DiskPart" in the search box and press "Enter". Click "Yes" to open the command prompt.
Step 2. Input "list disk" and press "Enter”.
Step 3. Input "select disk n" and press "Enter". (Note: n is the number of the disk you want to convert).
Step 4. Input "clean" and press "Enter" to delete all the partitions on the selected disk. If there are no partitions, skip this step.
Step 5. Input "convert mbr" or “convert gpt” and press ‘Enter’ to complete the conversion between GPT and MBR formats.
The above two methods allow you to convert an MBR disk to GPT (or vice versa), however, both of them require you to delete all of the disk partitions beforehand. Therefore, to avoid data loss, you should back up all important data beforehand. Or you can switch to third-party software to finish the conversion without deleting partitions.
Safest way to convert MBR and GPT without data loss in Windows 11/10/8/7
To convert disk between MBR and GPT while keeping inside data safe, we recommend you use AOMEI Partition Assistant Professional Edition. This powerful partition manager can convert both system disk and data disk to GPT or MBR without deleting partitions on the target disk. Moreover, you can directly convert a system disk within Windows (no need to enter the WinPE environment) as long as you can boot into Windows successfully. You can download the demo version to see how to convert MBR to GPT without reinstalling Windows in Windows 10.
If you plan to convert GPT to MBR, follow the instruction:
Step 1. Install it, and launch the program. In the main window, you should right-click on the disk that you want to convert and choose the "Convert to MBR" option.
Step 2. Click "OK" to continue.
Step 3. Click "Apply" to perform the pending operations.
After that, you have converted to GPT successfully. To convert GPT to MBR, just right-click the GPT disk and select the "Convert to GPT" option and then follow the steps to make it done.
To boot the PC successfully after the system/boot disk has been converted from MBR to GPT, please switch boot mode from Legacy BIOS to UEFI mode. You may need to check your PC (or motherboards) manual in order to find specific instructions on how to change the settings.
With three different methods shared, now you should know how to convert MBR to GPT in Windows 10/8/7. Obviously, AOMEI Partition Assistant Professional offers the securest way to convert a disk between MBR and GPT without deleting partitions so that you can get around the risk of losing data.
Besides, it comes with many other great functions like merging partitions, allocating free space from one partition to another, cloning MBR disk to GPT, or cloning GPT disk to MBR disk, and migrating OS to an SSD (or any other hard disk). To enjoy those amazing features on Windows Server, please try AOMEI Partition Assistant Server.