Do you know the differences between GPT and MBR in partitioning a drive? Let's go see them.
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When setting up a new disk in Windows 10 or Windows 11 you will be asked if you want to use MBR or GPT. We'll explain the difference between GPT and MBR and help you choose the right one for your computer.
The differences between MBR and GPT partitioning are pretty straightforward. However, there is a lot of basic information to help you get a clearer picture of each type of partition board and when you should choose one over the other.
Also both standards are not only mentioned for Windows as they can also be used on Linux, macOS and other operating systems.
In this article we'll look at what a partition is, the difference between MBR and GPT partitioning, whether you should upgrade from one partition type to another, and more.
What is Partition
A partition simply refers to how space is allocated (divided) on any type of storage device, such as hard drives, SSDs, and flash drives.
Most of the time you only have one partition per drive, but there are several cases where you need to have more than one. This is common in Windows and in fact on the drive where the C partition is: Basically you will find there another partition with data for restoring Windows.
Take for example “Disk 4” which has three partitions and one unused one.
In Linux, there is usually a root ( / ) partition, one for swap to help manage memory, and a large /home partition. The /home partition is similar to the Windows C: partition in that it's where you install most of your programs and store your files.
A partition structure (you'll also hear it as partitions) defines how the information on the partition is structured, as well as the code used at startup if a partition is bootable.
If you've ever partitioned and formatted a disk (example if you have two running on the same machine) you've probably had to choose between MBR and GPT. GPT is the new standard and is gradually replacing MBR.
What do GPT and MBR do?
Before a drive can be partitioned into individual partitions, it must be configured to use a specific partition scheme or table.
A partition table tells the operating system how the partitions and data on the drive are organized.
There are two main types of partition tables: MBR (Master Boot Record) and GPT (GUID Partition Table) are two different ways of storing the partition information on a drive. GPT is newer and is gradually replacing MBR.
This information includes where partitions start and end on the physical disk, so your operating system knows which sectors belong to each partition and which partition is bootable.
This is why you should choose MBR or GPT from scratch before partitioning a drive.
Differences between MBR and GPT
MBR was first introduced with IBM PC DOS 2.0, in 1983. MBR uses a bit of reserved space (some sectors) at the beginning of the drive that contains information about how the partitions are organized. The MBR also contains code to boot the operating system and is sometimes called the Boot Loader.
Boot Loader is a small piece of code that generally loads a larger boot loader from another partition. If you have Windows installed, the initial bits of the Windows boot loader are located here, so sometimes you may need to repair your MBR if Windows won't boot. If you have Linux installed, the GRUB boot loader will usually be located in the MBR.
MBR has its limitations. Only works with drives up to 2 TB in size. You can use a drive that is larger than 2 terabytes with MBR, but only the first 2 terabytes of the drive will be used. The remaining storage space on the drive will be lost.
MBR also only supports up to four primary partitions. If you want more, you need to make one of your primary partitions an “extended partition” and create logical partitions within it. This is a silly little hack and shouldn't be necessary.
GPT is a new standard that is gradually replacing MBR. It is connected to UEFI, which replaces the old BIOS with something more modern. So GPT, in turn, replaces the old MBR partition system with something more modern.
As MBR is older, it is usually associated with older legacy BIOS systems, while GPT is found in newer UEFI systems.
GPT is called a GUID Partition Table because each partition on your drive has a “universally unique identifier” or GUID, a random string so long that every GPT partition on Earth probably has its own unique identifier!.
GPT does not suffer from the limitations of MBR. GPT-based drives can be much larger, with size limits depending on the operating system and its file systems. Generally GPT reads a maximum capacity of 9,7 zetabytes.
GPT also allows for an almost unlimited number of partitions. Again, the limit here will be your OS, Windows allows up to 128 partitions on a GPT drive and you don't need to create an extended partition for them to work.
On an MBR disk, partition and boot data are stored in one place. If that data gets overwritten or corrupted, you're in trouble. Instead, GPT stores multiple copies of that data across the entire disk, so it's much more robust and can recover if the data is corrupted.
GPT also stores cyclic redundancy check (CRC) values to check that its data is intact. If the data is corrupted, GPT can notice the problem and try to recover the corrupted data from another location on the disk.
The MBR had no way of knowing if its data was corrupted, and unfortunately you'll only find out when the boot process fails or the drive's partitions disappear.
Compatibility
GPT drives tend to include a “protective MBR”. This type of MBR says that the GPT drive has a single partition that spans the entire drive. If you try to manage a GPT disk with an old tool that can only read MBR, it will see a single partition spanning the entire drive.
This MBR protector ensures that legacy tools will not mistake the GPT drive for an unpartitioned drive and replace its GPT data with a new MBR. In other words, MBR protector protects GPT data from being overwritten.
Windows can only boot from GPT on UEFI-based computers running 64-bit versions of Windows 11, 10, 8, 7, Vista, and corresponding server versions. All versions of Windows, from 11 to Vista, can read GPT drives and use them for data, they just can't boot from them without UEFI.
Other modern operating systems can also use GPT. Linux has built-in support for GPT. Apple's Intel Mac computers no longer use Apple's APT (Apple Partition Table) system and use GPT instead.
You will probably want to use GPT when setting up a drive. It is a more modern, powerful standard towards which all computers are moving.
But if you need backward compatibility, for example, the ability to boot Windows from a drive on a computer that has a traditional BIOS, you should stick with MBR for now.
Should you upgrade from MBR to GPT?
If one of your drives currently uses an MBR partition table, you may be wondering if you should upgrade to the newer GPT standard.
In short, probably not. As the saying goes, if it ain't broke, don't fix it.
It is very easy to corrupt the MBR sector of the drive, making it impossible to reboot. You will then need to either create a recovery USB drive with Windows or Linux and try to repair the MBR, or completely wipe the drive and reinstall the operating system.
But there are some cases where you might consider upgrading from MBR to GPT.
For example, you might want to upgrade your drive to a drive that is larger than 2 terabytes, or you need more than 26 partitions. Even in these cases, you should make sure that your hardware can support a GPT partition table and a UEFI BIOS.
Or change machine to a newer one and want to use your old Windows disk on it. Or you want to clone your hard disk with SSD and your machine supports bootable GPT.
Read related: Clone HDD disk to SSD
If you've done your research and are sure you want to make the jump to GPT, make sure you have a backup of your drive and all important data.
In the worst case scenario, you'll be able to restore without having to reinstall everything and start over.
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