By Emily / Last Updated December 22, 2021

“How do I clone a GPT disk?”

“I have a system installed on HDD - GPT partition. I want to transfer that GPT disk to a new empty SSD. The SSD is lightly smaller than the source disk. But what is the best way, to copy the GPT boot disk to the SSD, so that SSD will become bootable? When I initialize that SSD to MBR and copy the UEFI GPT System disk, will it work? Thanks for any hint!”

Why clone GPT disk to MBR disk?

A GPT disk is a disk that uses the GUID Partition Table format to define the hard disk partitions in the computer with UEFI startup firmware. It is considered as a replacement of the previous Master Boot Record (MBR) format that adopts the Legacy BIOS startup mode. GPT is more advanced than MBR with several significant advantages over MBR such as its supporting disk over 2TB, and about 128 primary partitions.

However, sometimes you might want to clone GPT disk to an MBR disk. For example, you got a new computer, but its motherboard does not support the UEFI boot mode, then you need to clone the GPT disk to an MBR disk to use the Legacy BIOS startup. Besides, GPT formatted system disk is only supported on 64-bit Windows operating system. If you are using a 32-bit Windows OS, you have to clone it from GPT disk to MBR disk.

Comparison Mbr And Gpt

How to clone a GPT disk in Windows 11/10/8/7?

After diving into the reasons behind copying GPT disk, now it is time to figure out how to clone GPT system disk to MBR disk. The easiest way is to use a professional disk cloning tool like AOMEI Partition Assistant Professional. This software is compatible with all editions of Windows  11/10/8/7 and Windows XP/Vista, and allows for GPT to MBR clone, GPT to GPT clone, MBR to GPT or MBR to MBR clone.

It provides “Clone Disk Quickly” and “Sector-by-Sector Clone” methods for disk clone. The former one is cloning only used space to the destination disk while the second one is cloning both unused and used space to the destination disk. If you are cloning GPT to a larger MBR disk, you can choose either one of them. To clone GPT to a smaller MBR disk, please choose the first method. Besides, to clone GPT disk to SSD, it allows you to align SSD partitions to optimize its performance. So, it is worth trying. You can download its demo version and check out the below steps.

Download Free Demo Win 11/10/8.1/8/7/XP
Secure Download

1. Steps to clone GPT disk to MBR

Before you do: if there are more than 5 primary partitions on the source GPT disk, you had better merge partitions to reduce the primary partition number under 4 because MBR disk supports 4 primary partitions at most or 3 primary partitions plus 1 extended partition.

Step 1. Connect the destination disk to your computer and make sure it is detected. Install and run AOMEI Partition Assistant Professional. Choose “All Tools” and “Disk Clone Wizard”.

Clone GPT Disk

Step 2. In the pop-up window, choose a proper way to clone GPT disk to MBR. Here we select the first one as an example.

Clone Disk Quickly

Step 3. Choose the GPT disk as the source disk and click “Next”.

Select Source Disk

Step 4. Choose the MBR disk as the destination disk and click “Next”.

Select Destination Disk

PS.: If you are cloning GPT disk to SSD, tick the option “Optimize the performance of SSD”.

Step 5. Here you can adjust partition size on the MBR disk. Then click “Next” to continue.

Resize Partition

Step 6. Then a boot note will appear. Read it and click “Finish”.

Boot Note

Step 7. In the main interface, click “Apply” to commit the pending operation.


Wait for the process to be done.

2. How to boot from the cloned disk?

After the cloning process is completed, you can remove the GPT disk from your computer and install the cloned MBR disk, change the boot mode from UEFI to Legacy in BIOS and your computer will boot from it. If you want to keep those two disks on your PC, you need to do as below:

Step 1. Reboot your computer and wait for the message during the POST (Power On Self Test) about a particular key (Del, ESC, F1, F2, F8, F10, etc), and then press the key as soon as you see in the message to enter BIOS.

Step 2. Use the arrow keys to access to the BOOT tab and Change Boot Order menu.

Step 3. Move the new system disk to the first position in the list.

Step 4. And disable UEFI and enable Legacy.

Enable BIOS

Step 5. Save and exit the BIOS setup utility and your computer will restart with the changed settings.

After making sure the cloned MBR is bootable, you can wipe the original system disk to free up disk space for new data via “Wipe Hard Drive” feature of AOMEI Partition Assistant Professional.

Wipe System Disk


So, with the powerful disk cloning software, it is very easy to clone GPT disk to MBR/GPT disk. If you just want to clone OS from GPT to another MBR or GPT disk, you can try “Migrate OS to SSD Wizard”, which will migrate only OS related partitions to SSD/HDD and ensure a secure boot. Additionally, it is also equipped with many other amazing features such as allocating free space from one drive to another, splitting a large partition into two smaller partitions, extending system drive without rebooting computer. To enjoy such functions on Server operating system, you can try AOMEI Partition Assistant Server.