By Dervish / Last Updated September 26, 2021

Convert MBR to GPT in Windows 7 to Better Utilize Disk

In general, computers’ hard drives are coming with Master Boot Record (MBR) partition style and boot in Legacy BIOS mode. This combination works quite well until the hard drive capacity becomes bigger.If you want to make full use of the disk that greater than 2TB, you have to convert MBR disk to another partition style called GUID Partition Table (GPT) in Windows 7.  And since Windows 11 has been released, which only supports UEFI mode to boot, users who want to use Windows 11 will have to choose GPT disk.

As we know, the MBR partition style supports creating partition on disk up to 2TB in size. The left disk space over 2TB will be marked as “Unallocated Space” and cannot be used to create new volume. For instance, you may find your 4TB hard drive only shows 2TB.

What’s more, one can only create up to either 4 primary partitions or 3 primary partitions and 1 extended partition on MBR disk. GPT partition style breaks this limit and allows you to create as many as you like on the hard disk, as long as the drive letter is available. So the main purpose of converting MBR disk to GPT in Windows 7 or later is to make the most of the hard drive. More differences about these two partition styles are introduced in MBR and GPT.

Many PCs now include the ability to use the UEFI version of BIOS, which can speed up boot and shutdown time and can provide additional security advantages. Now, let’s find out a way for Windows 7 convert MBR to GPT.

How to Convert MBR to GPT in Windows 7 without Data Loss?

There are many tools to convert from MBR to GPT, Windows Installation CD or USB Key, Command Prompt and Disk Management. However, to avoid data loss during the conversion, it is inevitable to turn to third-party partition manager. AOMEI Partition Assistant Professional is such a great tool that can help you complete the task. It is compatible with Windows 7, 10, 8/8.1, XP, Vista and has user-friendly interface. You can download the Demo to have a try. Other methods of converting will be discussed later.


Download Pro Demo Win 11/10/8.1/8/7/XP
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1.To convert MBR to GPT disk in Windows 7 without losing data, here you should install and launch AOMEI Partition Assistant. In the main interface, right click the disk and select “Convert to GPT Disk”

Convert System Disk To Gpt

2. Click “OK” in the pop-up dialog to confirm the operation. It will prompt you the GPT is boot from UEFI mode. Make sure your system support this mode.

Ok To Gpt System Disk

3. View the virtual result. The disk has changed to GPT disk from MBR and all partitions and data are kept. Click “Apply”>“Proceed” to commit the pending operations.

Apply To Gpt System Disk

Tips: To convert MBR to GPT in Windows Server i.e. Server 2008, Server 2012, Server 2016, it is a good idea to turn to AOMEI Partition Assistant Server edition.

Within three steps, you are allowed to convert Windows 7 MBR disk to GPT without deleting partitions. You can use the same way to convert GPT back to MBR when the need ever arises. Obviously, you can convert partition style between MBR and GPT with other tools. Following introduces situation that you don’t need to boot Windows OS while converting.

Convert MBR to GPT without Windows Boot-Up

It is not uncommon to convert disk partition style without booting Windows operating system. When installing Windows on bare metal, you might need to convert MBR to GPT to fit your PC UEFI boot mode. When computer fails to boot, creating a bootable device to convert partition style saves conversion time and reduce affecting factors.

How to Convert MBR to GPT during Windows Installation?

When installing Windows on UEFI-based PCs using Windows setup, the hard drive partition style should be set up to support UEFI mode, i.e. GPT partition style. For instance, when you get the error messages reads: Windows cannot be installed to this disk. The selected disk is not of GPT partition style. Meaning your PC is booted in UEFI mode but your hard drive is not configured for this mode. Follow these steps to make a change to your hard drive partition style. This method also is a way to convert MBR to GPT using Diskpart in CMD.

1. Turn off your PC and insert the Windows Installation DVD or USB key. Boot from the device. At the Windows Setup, press + to open Command Prompt window.

Command Prompt

2. Type diskpart and press. Input below orders in sequence.

list disk
select disk n (n is the disk number of the hard drive you want to convert)
convert gpt

Please note that this method will wipe all data on the selected hard drive. Please backup important databefore you start.

Above method is a way to take advantage of Windows Installation tool during installation. If you don’t have an installation tool in hand, maybe you can turn to next method to change partition style before clean install or system recovery.

Make Bootable Media to Change MBR to GPT in Windows 7

Aforementioned software – AOMEI Partition Assistant Professional is capable of creating bootable media with WinPE-based or Linux-based OS on. The bootable media has the software pre-installed, so every feature of that software is available.

Step 1. Plug in a USB drive or CD/DVD. Run AOMEI Partition Assistant and go Make Bootable Media.

Make Bootable Media

Step 2. This tool will detect if your computer needs to install Windows AIK or not automatically. If needed, please install it first. Then select target USB or CD.

Choose Usb Drive

Step 3. Wait for the process to be completed and click “Finish”.


Step 4. Turn off the PC and boot it from the created bootable device (you may need to change boot priority in BIOS for this). Then, all steps left are same as converting MBR to GPT without losing data covered before.

Other Things You May Want to Know

When it comes to change hard drive partition style between MBR and GPT, there are two points you may need to pay attention to.

Conversion on Data Disk vs. Conversion on System Disk

Converting partition style on system disk is a little different from converting on data disk. Windows only converts empty MBR disk to GPT partition style, otherwise, the disk will be auto changed to dynamic disk. In Disk Management and CMD, you can delete or wipe all partitions on data disk to perform converting, yet you cannot do this to system disk. Obviously, Windows won’t allow you to do something harmful to it like deleting or formatting. One can only try the “convert without booting Windows methods” under such circumstances.

MBR and BIOS vs. GPT and UEFI

Generally speaking, there are two boot mode + disk partition table combinations: MBR + Legacy BIOS and GPT + UEFI. Legacy BIOS cannot recognize GPT partition style, yet UEFI supports both MBR and GPT disk. Nevertheless, Microsoft wants operating system to be installed on GPT disk when booted in UEFI mode. Surely, in most cases, you need to change partition table to adapt to the correspondent boot mode.


When you want to convert MBR to GPT in Windows 7, 8 or 10, you know you have more than one choice. Windows Installation tool is simple and easy in fact. However, if you want to keep installed system and applications saved, AOMEI Partition Assistant is a good tool to meet this need. It also supports convert file system without formatting between FAT32 and NTFS.