By Bryce / Last Updated April 26, 2023

Can I clone MBR to GPT SSD directly?

“I have a 500GB MBR partitioned disk with Windows 10 installed on. I want to replace it with my newly purchased 1TB GPT partitioned SSD while I don’t want to reinstall Windows and all other applications on GPT SSD? Can I just clone my MBR system disk to GPT disk directly and boot from the cloned drive without failure?”


Before making a decision of duplicating the MBR disk to GPT, it's wise to have a basic understating of the differences between MBR and GPT disks.

▶ GPT supports disks larger than 2 TB in size while MBR cannot.

▶ The GPT disk partitioning style supports volumes up to 18 exabytes in size and up to 128 partitions per disk. The MBR disk partitioning style supports volumes up to 2 terabytes in size and up to 4 primary partitions per disk (or three primary partitions, one extended partition, and unlimited logical drives).

▶ GPT disk provides greater reliability due to replication and cyclical redundancy check protection of the partition table. Unlike MBR partitioned disks, data critical to platform operation is located in partitions instead of unpartitioned or hidden sectors.

▶ GPT partitioned disks have redundant primary and backup partition tables for improved partition data structure integrity.

Legacy BIOS, an essential firmware can activate all necessary components for boot. It is gradually replaced by UEFI (Unified Extensible Firmware Interface). UEFI supports GPT disk and boots OS faster since it omits the testing process. The Legacy BIOS will wake up the hardware first, and then load the bootloader to initialize Windows, so it needs a longer time to execute the boot preparation.

Boot process

If your OS is 64bit and the computer motherboard supports UEFI boot mode, it's wise to clone the MBR system disk to GPT and then use UEFI boot mode, especially if you have a plan to upgrade to Windows 11 in the future. To check whether your PC support both Legacy and UEFI, enter the System Information window (press Windows +R, input "msinfo32" and click "OK")and view BIOS Mode. Here we make a simplified list of the system and the partition style.

Windows OS list

How to clone MBR to GPT disk without boot failure?

Make sure that the OS supports GPT disk and the motherboard supports UEFI boot mode. Then, you can easily clone (system) MBR disk to GPT SSD/HDD via a disk cloning tool, AOMEI Partition Assistant Professional

It can clone MBR disk to GPT SSD or HDD without requiring you to convert the destination GPT disk to MBR partition style and It allows you to clone GPT disk to MBR as well.
It supports you to transfer only OS-related partitions as well (not including data partition) from MBR disk to GPT disk via Migrate OS to SSD function. 
It can make a 4K alignment to improve SSD’s performance during the cloning process.
The Professional edition is for Windows 11/10/8.1/8/7 and you can use AOMEI Partition Assistant Server if you are using Windows 2022, 2019, 2016, 2012, or 2008.

You download its demo version to have a try!

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

Now, connect the GPT SSD to your computer and make sure it can be detected. Install the software and have a look at how it clone MBR to GPT SSD:

Step 1. Run AOMEI Partition Assistant Professional and click “Clone Disk” in the right menu.

Disk Copy Wizard

Step 2. A window will pop up. Here you can choose a way to copy the MBR disk to GPT based on the specific situations. Here I choose Clone Disk Quickly. To clone the BitLocker encrypted hard drive, you need to choose the second option.

Copy Disk Quickly

Step 3. Choose the MBR system disk as the source disk.

Select Source Disk

Step 4. Select the GPT disk as the target disk. When it is SSD, check “Optimize the performance of SSD…

Select Destination Disk

Step 5. Here you can edit partitions on the target disk.

Edit Disk

You’ll be prompted by a note about how to boot the operating system from the target disk. Read and remember it. Then, click “Finish”.


Step 6. You’ll be in main interface. Confirm your operation and click "Apply">"Proceed" to execute it.


▪ When you clone MBR disk to a larger GPT disk, there might be unallocated space after cloning, you add the unallocated space to another drive or create a new partition with the unallocated space to make full use of it.
▪ After making sure that you can boot the computer from the GPT destination disk, if you want to give up your old MBR source disk, you can use AOMEI Partition Assistant Professional to wipe the old hard drive completely and irrevocably.

Follow-up work after MBR to GPT disk copy

After cloning the MBR disk with OS installed to GPT, since the boot mode for MBR and GPT is different, you need to change the boot mode from Legacy to UEFI:

1. Reboot your computer and press a functional key (usually, F1, F2, F3, or F10) repeatedly to enter the BIOS setup when you see the first screen. 

2. Under the BOOT tab, choose UEFI/BIOS Boot Mode and change the Legacy to UEFI. Then, save and exit the interface. 

Change boot mode


PS.: If you want to keep both the old disk and new disk, to boot from the target drive, you also need to set the new drive as the prior boot device in BIOS.