By Catherine / Last Updated August 19, 2019

You might be asked to choose MBR or GPT when you initialize a disk for the first time in Windows. Many computer users do not know which one to choose since Windows does not provide extra useful information about them. But don’t worry. You’ll have a basic understanding about MBR vs GPT after reading this page.

GPT is the abbreviation of GUID Partition Table, which is a standard for the layout of the partition table on a physical hard disk, using globally unique identifiers(GUID). MBR is another kind of partition table formats. MBR stands for master boot record.

MBR is old, GPT is new. But the new is not always better than the old. There are still many vendors utilize the MBR technology since it is still predominantly used in the real world. GPT disks have advantages of partition size, number of partitions, and resilience. If a computer that uses UEFI, it will only support GPT. So when you upgrade your computer, it may be necessary to convert MBR to GPT at first.

A MBR disk can be basic or dynamic, just like an GPT disk can be basic or dynamic. Compared with MBR disk, a GPT disk performs better in the following aspects:

  • 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 while 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 (CRC) 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.

MBR and GPT

For more information about the differences between GPT disk and MBR disk, please go to: The Differences betwwen MBR and GPT.

Usually, MBR and BIOS (MBR + BIOS), and GPT and UEFI (GPT + UEFI) go hand in hand. This is compulsory for some operating systems (eg. Windows), while optional for others (eg. Linux). When considering convert disk to GPT disk, make sure that your computer’s motherboard supports UEFI boot mode.

How to Convert GPT or MBR in Windows Accordingly?

After learning information about MBR and GPT, you may find that it is better for you to convert MBR or GPT to take advantage of hard disks. Here in Windows, basically you have two ways to complete, Windows built-in tools and third-party software.

Convert to GPT Disk via Windows Built-in Utilities

With Windows Disk Management and Diskpart tools, you’re allowed to convert an EMPTY hard disk to MBR or GPT with ease. That is to say, you need to delete all existing partitions in the first place. Therefore, back up important data to a safe place in advance. Here takes convert to GPT using Diskpart for example.

1. Press Windows key + R key simultaneously to lift Run box. Input “diskpart” and press Enter.

2. At DISKPART prompt, input following commands successively and each command follows a Enter pressing.

  • list disk

  • select disk n (where n is the disk number of target disk)

  • clean (this command will erase entire disk)

  • convert gpt (or convert mbr)

  • exit

Diskpart Convert GPT

Notes: You may not convert system disk to GPT under Windows environment since this operation requires no partitions stored.

Convert to GPT or MBR without Losing Data (System Disk Included )

Next I’d like to tell you a good way to convert MBR to GPT without data loss. That is with AOMEI Partition Assistant Professional. The powerful hard drive manager allows you to convert between MBR and GPT on both system disk and data disk without deleting partitions in simple clicks. Here is a step-by-step guide.

In the first place, download AOMEI Partition Assistant Professional Edition from its office website. Install and run. Here I will take convert MBR to GPT for example.

Step 1. Right click the MBR disk that you want to convert to GPT and choose Convert to GPT Disk.

Convert System Disk to GPT

Step 2. You'll be asked that "are you sure to convert the selected disk from MBR to GPT disk?". Click OK.

OK to GPT System Disk

Step 3. To commit operation, please click Apply, and then click Proceed.

Apply to GPT System Disk

Notes:

  • A removable disk is not allowed to converted into a GPT disk.

  • Converting system disk to GPT partition style requires 64-bit operating systems. Note that Windows XP 64bit can only use GPT disk for data storage.

How about Converting GPT to MBR Disk?

There are some situations need convert GPT to MBR. One is like the problem - “the Selected Disk is of the GPT Partition Style” when people install Windows system. People can also convert GPT to MBR disk by the aid of AOMEI Partition Assistant Professional Edition.

Convert System Disk to MBR

To avoid repetition, it’s not described in this article. Please visit: How to convert GPT to MBR?

Some FAQs You May Concern

  • Is Windows 10 GPT or MBR?

From the reliability and CRC protection mentioned before, it is suggested to use GPT partition style if all other conditions are qualified.

  • Should my SSD be MBR or GPT?

Usually, SSDs are used to install operating systems. All Windows operating systems can be installed on MBR disks yet some of them cannot be installed on GPT disk. Windows 8 and higher operating systems are required as shown in the first figure.

  • Can UEFI boot MBR?

Yes. UEFI supports the traditional master boot record (MBR) of hard drive partition, but you may not use Legacy boot GPT on the contrary.

Conclusion

In any event, with the help of AOMEI Partition Assistant, anything will be easier. It can be a great partition converter, not only between MBR and GPT, but also FAT and NTFS, primary partition and logic partition. It can even rebuild MBR when the master boot record corrupted.