How to Convert HDD to GPT in Windows 10/8/7? [Without Data Loss]

December 17, 2018

If you need to convert hard disk drive (HDD) from MBR to GPT partition style, refer to this paper and you can learn how to convert disk to GPT without losing data.

MBR VS GPT

MBR, short of Master Boot Record, and GPT, short of Globally Unique Identifier Partition Table are two kinds of partition style:

  • MBR only support disk whose size is under 2TB. If the storage of it is over 2TB, the space of the MBR disk will only show 2TB. MBR disk supports up to four primary partitions or three primary partitions plus one extended partition. Extended partitions can be subdivided into multiple logical partitions.

  • GPT disk breaks out the limitation of 2TB disk space and 4 primary partitions. But GPT disk also has limitations as well. All Windows versions can use GPT disk as data storage device. But only 64bit versions can be installed on GPT disk; at the same time, your computer motherboard should support EFI/UEFI mode or Legacy BIOS-compatibility mode.

Why convert HDD to GPT?

The main reasons of converting hard disk drive (HDD) are concluded as follows:

  • Make full use of large HDD beyond 2TB. If a MBR HDD is beyond 2TB, the beyond size will not showing and be used. Some issues like 4TB hard drive only showing 2TB or external hard drive only shows half capacity will appear. Thus, you need to convert HDD from MBR to GPT.

  • Create more partitions on HDD. MBR HDD only allows you to create four primary partitions or three primary partitions and one extended partitions. To create more partitions to store different files and manage disk effectively, it is wise to make conversion from MBR to GPT.

  • Solve Windows installation error. On EFI systems, Windows can only be installed to GPT disk. If you install it on MBR, you can get an error message: Windows cannot be installed to this disk. The selected disk has an MBR partition table” In such condition, you should convert disk to GPT.

Two effective ways to convert MBR HDD to GPT

Here offers you three valid & safe ways to help you to convert MBR HDD or SSD to GPT partition styles and you can choose one according to your specific demand.

Convert disk to GPT via a third party MBR to GPT converter (without deleting)

The first method about converting HDD or SSD to GPT is using a 3rd party MBR to GPT converter – AOMEI Partition Assistant Professional. It is compatible with Windows 10/8.1/8/7, XP and Vista and with concise and simple graphic user interface. It not only allows you to change data disk from MBR to GPT, but also to convert system disk to GPT without data loss. Have a look at how it works (Take converting system HDD to GPT in Windows 10 as an example):

Step 1. Install and run AOMEI Partition Assistant Professional. In the main console, locate the HDD that you need to convert, right click it and choose "Convert to GPT Disk".

Convert HDD to GPT                        

Step 2. It will ask you that are you sure to convert the select disk from MBR to GPT, click “OK”. Then, confirm that your system support EFI/UEFI mode and click “Yes” button.

OK

Step 3. You’ll be back to the main console. Here you can review the operation. Then, click Applyto execute it.

Notes:

  • After converting successfully, you need to enter BIOS to change Legacy to EFI/UEFI.

  • You can also use this software to convert disk from GPT to MBR without losing data.

Convert disk to GPT using diskpart (with deleting)

The second way will be introduced you is using a Windows built-in tool, Diskpart. This tool allows you to convert an empty HDD or SSD from MBR to GPT. That is to say, you need to remove all partitions on the disk if there are partitions on the disk, in order to make conversion. If you don’t want to lose data on the disk, you can back up it in advance. Then, follow the steps below to convert MBR disk to GPT.

Step 1. Press Windows + Rat the same time, input diskpart and hit Enter to access Diskaprt interface.

Step 2. In this window, run the following commands:

  • list disk

  • select disk n, n refers to the number of the MBR disk

  • clean

  • convert gpt

Diskpart Convert to GPT

Step 3. After converting MBR disk to GPT, exit from this window.

PS.: You can also turn to another Windows built-in tool, Disk Management, to convert MBR to GPT. But you still need to delete all partitions on it; otherwise, you’ll see the option of Convert to GPT Disk greyed out.

Wrap things up

Having realized different ways for converting HDD to GPT or SSD to GPT partition style, you can apply a proper one under various conditions. If you are familiar with Windows and have no fear of complicated process, you can employ Diskpart utility. If you are a green hand and don’t want to backup and restore files on the disk, AOMEI Partition Assistant Professional will be your choice.

In fact, it can be helpful in fixing many issues For example, if you have accidentally deleted recovery partition, it is capable of recovering partitions; if your C drive is full after update, it enables you to extend C drive even without losing data.