Clone MBR to GPT SSD or HDD in Windows 10 or 11 Safely

This post shows how to clone MBR to GPT disk (SSD or HDD) safely in Windows 11/10/8/7 and tells how to change boot mode from BIOS to UEFI after cloning.

Posted by @Bryce December 17, 2024 Updated By @Bryce July 31, 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?”

There’s one common question for PC users: whether it is possible to clone an MBR system disk directly to a GPT disk, without the need for a reinstallation. Fortunately, the answer is yes.

When you find that your old hard disk is running out of space, replacing it with a larger one can greatly enhance system performance. Specifically, if you desire to boost the speed of your computer, the most effective method is to replace the current drive with an SSD.

For older computers, it is always used to utilizing the MBR partition style. If you intend to successfully boot the SSD, it is necessary to clone the MBR along with the SSD. Let's explore this further.

MBR VS GPT & Legacy VS UEFI

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.

▶ Part 1. MBR vs. GPT

The MBR (Master Boot Record) and GPT (GUID Partition Table) are two distinct types of partition tables that are widely utilized in Windows systems. These partition tables serve the purpose of describing the partitions present on a hard disk drive (HDD) or solid-state drive (SSD), aiding in the identification and retrieval of files by the operating system. However, there are notable differences between MBR and GPT:

▶ 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.

▶ Part 2. Legacy vs. UEFI

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.

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.

How to choose a reliable software to clone MBR to GPT SSD

To successfully perform the task of cloning MBR to GPT SSD, reliable disk cloning software is in requirement. But how to choose the most trust-worthy tool in the market? Here, you can get some ideas. The target tool need to have the following basic ability:

➹ Clone compatibility

Ensure that the software supports cloning between different partition styles, specifically MBR and GPT disks. This flexibility allows you to clone from MBR to GPT or vice versa without requiring prior conversion.

➹ Disk size flexibility

Look for software that intelligently handles disk sizes. The ideal tool should have a default mode that copies only used data, enabling you to clone a larger drive to a smaller one. Additionally, if your GPT disk is larger, the software should offer a function that allows you to copy every bit of data.

➹ Additional clone options

A reliable cloning tool should provide useful options to maximize disk space utilization and facilitate the conversion of the destination disk's partition style if needed. Look for features like partition resizing and the ability to optimize SSD performance.

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, according to the standard of choosing a powerful MBR to GPT SSD migrator, we highly recommend AOMEI Partition Assistant Professional to clone (system) MBR disk to GPT SSD/HDD easily.

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 can download its demo version to have a try!

Free Download 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.

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.

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

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

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

Notes: ▪ 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. 

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. 

Frequently Asked Questions (FAQs) about cloning MBR to GPT SSD

☀ Can I clone an MBR disk to a smaller GPT SSD?

Yes, you can clone an MBR disk to a smaller GPT SSD as long as the data on the MBR disk can fit within the available space on the GPT SSD.

☀ Will cloning my MBR to a GPT SSD cause data loss?

When done correctly using a reliable cloning tool, the cloning process should not cause any data loss. However, it is always recommended to create a backup before proceeding.

☀ Can I convert an MBR disk to GPT without cloning?

Yes, you can convert an MBR disk to GPT without cloning by using built-in Windows utilities like Disk Management or the MBR2GPT tool. However, this method involves more manual steps and may require additional configuration.

☀ Do I need to reinstall my operating system after cloning MBR to GPT?

In most cases, you do not need to reinstall the operating system after cloning MBR to GPT. The cloned GPT SSD should be bootable, and your system should function normally.

Last line

Cloning an MBR to a GPT SSD may seem like a complex process, but with the right tool and detailed guidance, it can be accomplished smoothly. By following the steps outlined in this article, you can successfully clone your MBR disk to a GPT SSD with AOMEI Partition Assistant, ensuring data integrity and compatibility with modern systems.

By the way, AOMEI offers other impressive capabilities, such as moving installed programs, making bootable media, resetting Windows password, recover lost files, and so on.