[Stepwise] How to Convert MBR Disk to GPT without Losing Data in Windows

Why convert MBR disk to GPT?

Every hard drive relies on one basic element to organize its contents: the partition table. This table provides an intricate overview of the various parts of the drive, helping your system find important files.

In the world of Windows operating systems, the choice between Master Boot Record (MBR) and GUID Partition Table (GPT) depends on your specific operating system and firmware. After digging into user preferences, a common tendency emerged - wanting to convert MBR disk to GPT, especially if their Windows systems meet the necessary criteria.

The motivations behind this shift are worth exploring, and the following insights shed light on the underlying reasons.

✐ GPT supports larger drives. GPT supports impressive capacities of up to 18 EB, in contrast to MBR's 2 TB cap.

✐ GPT offers a wider partition canvas. GPT can accommodate up to 128 primary partitions, while MBR's limit is up to 4 primary partitions or 3 primary partitions and 1 extended partition.

✐ GPT has better support for newer operating systems. GPT integrates with later OS versions such as Windows 11 and Windows 10 64-bit, while MBR supports much older OS versions.

✐ GPT enhances data integrity. GPT provides a backup of the partition table at the end of the disk. This strategic layout minimizes the risk of data loss due to partition table corruption.

✐ GPT is required for systems using the Unified Extensible Firmware Interface (UEFI). UEFI replaces the legacy BIOS associated with MBR, and mandates the use of GPT.

The best way to convert MBR disk to GPT without data loss

How to efficiently convert MBR disk to GPT without losing data is a crucial task. While Windows built-in utilities like Disk Management or Diskpart require the deletion of existing volumes, resulting in potential data loss.

In this case, if you want to convert MBR disk to GPT without data loss, you are suggested to use a reliable alternative that allows for a seamless transition - AOMEI Partition Assistant Professional.

This trustworthy partitioning tool proves to be quite valuable as it can convert the system disk and data disk to GPT or MBR without erasing the partitions on the target disk.

Its versatility extends to 1-click OS migration to a new SSD, and disk cloning & upgrades. It is designed for users of all proficiency levels and runs seamlessly on Windows 11/10/8.1/8/7.

To ensure a smooth conversion without data loss, please follow these steps:

Step 1. Install and launch this tool. Right-click the MBR disk that needs to be converted and select Convert to GPT, or select the disk and select Convert to GPT from the right column.

Step 2. A pop-up window will ask "Are you sure to convert the selected disk from MBR to GPT disk?" Click OK to continue.

Step 3. Click Apply and Proceed to save the changes, and your disk will seamlessly transition to the GPT disk style.

Another 3 Windows built-in tools to convert MBR disk to GPT

Explore the alternatives for how to convert MBR to GPT disk outlined in this article. It is important to realize that choosing these three solutions may result in data loss if partition backup is ignored.

Way 1. Convert MBR disk to GPT with Disk Management

Use Disk Management (DM) to convert MBR to GPT, keeping in mind that this process involves deleting all partitions on the disk. Before proceeding, make sure to take a preventive backup of your drive or be prepared to recover any deleted or lost partitions after conversion.

To convert MBR to GPT:

Step 1. Right-click This PC/My Computer, select Manage, then navigate to Disk Management.

Step 2. Right-click the volume on the target disk and select Delete Volume....

Step 3: Once the disk is empty (shows as unallocated space), right-click on the disk and select Convert to GPT Disk.

Way 2. Convert MBR disk to GPT via Diskpart

Similar to using Disk Management (DM), the Diskpart tool requires the deletion of all files and folders on the hard drive. Please ensure a thorough file backup before proceeding with the following steps for MBR to GPT conversion using Diskpart in CMD.

Step 1. Type cmd in the search box, right-click Command Prompt, and select Run as administrator.

Step 2. Open Command Prompt, type diskpart and press Enter.

Step 3. Type list disks and press Enter. (note the disk number you want to convert to GPT)

Step 4. Type select disk 1 and press Enter. (Replace 1 with the number of your MBR disk.)

Step 5. Now, type clean and press Enter. (This command will delete all files and partitions from the hard drive, emphasizing the need to back up critical files beforehand.)

Step 6. Type convert gpt and press the Enter key to start the MBR to GPT conversion process.

Step 7. When completing these commands, type exit and press Enter to close the window.

Way 3. Convert MBR disk to GPT using MBR2GPT.exe

MBR2GPT.exe is a Windows built-in tool designed for how to change from MBR to GPT. Notably, it has the advantage of keeping files safe on disk during conversion. However, based on user feedback, caution is recommended as it is a complex tool with potential issues. Additionally, it is only available in Windows 10 version 1730 and above.

If you choose to continue using this tool and are confident in its use, please follow these steps:

Step 1. Run the command prompt with administrator privileges by typing cmd and selecting Run as administrator.

Step 2. Enter the following command at the command prompt and press Enter:

mbr2gpt /convert/disk:X /allowfullos

(X refers to the number of your MBR disk.)

Final words

After reading this guide, you will find that among the 4 solutions provided, utilizing AOMEI Partition Assistant Professional is the easiest way to convert MBR disk to GPT or vice versa without causing data loss. Its capabilities go beyond conversion and support tasks such as allocating free space to drives, rebuilding MBR, and managing UEFI boot options.

For users who prefer to use Disk Management or DiskPart for MBR to GPT conversion, an important reminder is to perform a thorough disk backup before starting the process. Instead, if you choose MBR2GPT.exe, you must ensure that your disk meets the specific requirements outlined by Microsoft. Failure to adhere to these prerequisites may cause the conversion to be unsuccessful, resulting in errors.