By Dervish / Last Updated March 3, 2022

Why migrate MBR OS to GPT disk?

MBR and GPT are two different partition styles. And in some aspects, the GPT is better than the MBR format. For example, it can support 2 TB+ hard drive and contain up to 128 primary partitions. Besides, the GPT disk uses the UEFI boot mode, which is relatively advanced than the Legacy BIOS.UEFI can directly boot OS after initialization and skip the BIOS self-test process, finally leading to a faster boot. So many users want to move OS from MBR to GPT disk to enjoy more effective disk space and optimize PC performance. In addition, Windows 11 released by Microsoft this year, only supports UEFI boot mode. So you can convert the system disk from MBR to GPT for Windows 11 or migrate the system disk from MBR disk to GPT disk.

Boot Process

Choose a reliable MBR to GPT migration tool

To finish the OS migration from MBR disk to GPT disk, the fastest and easiest way is to choose a reliable MBR to GPT migration tool. Here we would like to recommend the AOMEI Partition Assistant Professional (suitable for Windows 11/10/8/7/Vista/XP users). Its “Migrate OS to SSD” can migrate system partitions from one disk to another. And its operation is very simple, it only takes five steps to complete. After migration, not only the target disk can be booted, but no data is lost.

What’s more, AOMEI Partition Assistant is far more than a migration tool, it is also an MBR to GPT convert tool. If you want to convert system partition from MBR to GPT without data loss, this partition manager can also solve it for you. Please download the demo version to see how to migrate MBR OS to GPT disk.

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

How to migrate MBR to GPT via partition manager?

Now, I will demonstrate how to migrate MBR OS from MBR to GPT disk with AOMEI Partition Assistant Professional for you. Of course, before proceeding, please check whether your motherboard supports UEFI boot mode and make sure it can be enabled in the BIOS. Otherwise, your PC will not start up normally.

Step 1. Install your GPT disk in your computer or connect it with a SATA-to-USB adaptor and ensure it is recognized. 

Step 2. Run AOMEI Partition Assistant Professional and you can see all the partitions and disks available. Make sure the GPT disk has some unallocated space. If it does not, you can shrink or delete partitions on it to generate some such space. Then select the option “Migrate OS to SSD”.

Migrate Os Wizard

Step 3. In the next pop up window, select the unallocated space on the GPT disk as destination location.

Select Disk Space

Step 4. In the next screen, you can adjust the partition size on the disk if needed and then click “Next”. You can also resize system partition after the migration without data loss.

Resize Partition

Step 5. Here comes a note on how to boot from the destination disk. Read it and click on “Finish”.

Boot Note

Step 6. Preview the partition layout and click "Apply" to apply all operations if no problem.


The process will be complete under “AOMEI Pre-OS mode”, which will restart your computer, so save everything you are editing before the migration. After you migrate MBR OS to GPT disk, make sure you have enabled UEFI boot mode in BIOS before trying to boot computer from the GPT disk.


This is the whole process to migrate MBR OS to GPT disk and boot from it without any issues. If you have any partition-related issues, or you want to experience Windows 11, then this partition magic will definitely be your perfect assistant. By the way, Windows Server users need to upgrade to AOMEI Partition Assistant Server.