How to Convert MBR to GPT Without OS in Windows 7/10

You may need to convert a disk from MBR to GPT during Windows Installation or other reasons. Acturally, there are three ways for you to change MBR to GPT: Disk Management, DiskPart or third-party software. Read on to get the details and apply the way you prefer to convert MBR to GPT with ease.

How do I change a disk from MBR to GPT in Windows 11/10? This page includes two practical and reliable methods to help you easily convert MBR to GPT. This EaseUS page tells you the complete procedure for changing MBR to GPT without booting up the operating system. So, if you are about to switch your computer disk from MBR to GPT without an OS, this tutorial guide could be your best guide. Let's start to view the details.

Convert MBR to GPT Without an Operating System - No Data Loss

1. 🚩Complex Level: Simple
2. 🧰Tools Required: Windows computer, USB or external disk drive, disk conversion software - EaseUS Partition Master

EaseUS Partition Master is a reliable disk conversion tool that converts your disk from MBR to GPT directly in only a few clicks. What matters the most is that EaseUS Partition Master simplifies converting MBR to GPT without OS for Windows users at all levels.

It also exceeds Windows disk utilities like Disk Management and DiskPart in the following two aspects:

• ✔️Keep All Partitions: It doesn't require partition deletion for disk conversion.
• ✔️No Data Loss: This software keeps all data safely stored on the disk while converting it from MBR to GPT.

Take a view and follow the tips here to learn how to accomplish the operation - MBR to GPT conversion without OS:

1️⃣Connect the USB/External Disk to a New Healthy PC

To accomplish the process smoothly, ensure you have a running and healthy computer and connect an empty USB flash drive or an external USB disk to the computer.

• Connect or plug in USB to PC via USB ports.
• Format and set the USB drive to FAT32 file system format.

2️⃣Create a Bootable USB and Convert MBR to GPT without Operating System

To do so, you need to install EaseUS Partition Master on another healthy computer first. Then, create a bootable disk on a USB drive, boot the PC from the disk, and convert MBR to GPT without the operating system or during Windows installation.

Here are the detailed steps for you to follow:

Step 1. Connect an empty USB flash drive, or a CD/DVD disc to a healthy computer, launch EaseUS Partition Master, click "Bootable Media" and select "Create bootable media". Click "Next" to continue.

Step 2. Choose the USB or CD/DVD and click "Create" to start create the bootable media.

Step 3. Connect the USB with bootable media to your PC and restart the computer from EaseUS bootable media.

Press F2/Del to enter BIOS and set the computer to boot the PC from "Removable Devices" (bootable USB disk) or "CD-ROM Drive" (bootable CD/DVD). Press "F10" to save and exit to restart PC into EaseUS bootable media.

Step 4. Once your PC enter EaseUS Partition Master, go to Disk Converter and select "Convert MBR to GPT". Click "Next" to continue.

Step 5. Select the target MBR disk you tend to convert to GPT and click "Convert" to start the conversion.

After this, your disk will now have a GPT partition style, and you may continue installing Windows on the computer and make use of it for gaming or working by then.

Read Also: EaseUS Partition Master also helps switch disks from GPT to MBR without booting them into Windows. If you are also interested, follow this guide for help.

MBR to GPT Conversion Without OS Using CMD/DiskPart

1. 🚩Complex Level: Complex
2. 🧰Tools Required: Windows computer, USB or external disk drive, Windows installation media, CMD/Diskpart

The other way that you can switch MBR disk to GPT without the operating system is by using CMD or Diskpart command lines through a Windows installation media.

Then follow the steps below to convert your MBR disk to GPT:

Step 1. Create Windows installation media to a USB or external disk:

• Download Windows ISO from Microsoft's official site on a healthy PC.
• Double-click the ISO image and select "Create installation media."
• Select Windows editions and language, and select USB as the media.
• Wair for the procedure to accomplish.

Step 2. Boot target PC from USB installation media.

• Reboot the PC, press Del/F2/F8 to enter BIOS, and set the PC to boot from the USB installation media.
• Set and click to install Windows via USB, then press Shift + F10 to bring up Command Prompt windows.
• Right-click "Command Prompt" and choose "Run as administrator."

Step 3. Convert MBR to GPT without OS in CMD with DiskPart command lines.

• Type diskpart and hit Enter.
• Type list disk and hit Enter.
• Type select disk 2 and hit Enter.(Replace 2 with the disk number of your MBR disk.)
• Type clean and hit Enter.
• Type convert gpt and hit Enter.

DiskPart will delete all the partitions on your disk and then convert it to GPT.

Step 4. Type exit when the conversion process completes. 

After this, you can use the new GPT disk to create partitions, install a new Windows system, etc., without any obstacles.

Bonus Tip: Enable UEFI Mode After Convert System Boot Disk to GPT

If you converted a Windows system disk from MBR to GPT without booting into the OS, remember to enable the UEFI boot mode on your computer to make the entire computer boot up smoothly. Here are the steps:

Step 1. Restart the PC and press F2, F8, F12, and Del to enter the BIOS boot menu.

Step 2. Locate the boot options menu and enable the UEFI mode.

• Set Launch CSM to Enabled. If CSM is Disabled, you can skip to Step 4 below.
• Set Boot Device Control to UEFI Only
• Set Boot from Storage Devices to UEFI driver first

 

Step 4. Save the changes, exit BIOS, and reboot the PC from the GPT disk.

After this, wait patiently. Your computer will automatically reboot from the GPT disk by then. Don't forget to share this comprehensive MBR to GPT conversion tutorial with more users:

BONUS: Turn to Manual Service and Fix MBR to GPT Conversion Without OS

As for some Windows beginners, it's wise to request a manual service to eliminate the MBR to GPT conversion task without an OS on a computer. If you are one of those people with such an issue with installing Windows, relax, and EaseUS experts will assist you in resolving this issue efficiently.

When Do You Need to Convert MBR to GPT Without Operating System

As Windows partition styles, both MBR (Master Boot Record) and GPT (GUID Partition Table) are widely used in storage devices like your computer hard drives. With the release of newer operating systems, more and more users are changing their disks from MBR to GPT even without booting into OS.

Relax if you are with a similar case as the above example, also, don't worry if you are not quite clear about when to convert MBR disk to GPT disk without OS. Check the list here. If you are in one of the listed situations, take the provided methods above to change MBR to GPT:

• 1. Your computer is shipped without OS, and you must convert a disk to GPT for Windows installation.
• 2. The computer is installed with Windows 10 or 11, but you converted the OS disk to MBR by mistake.
• 3. To install Windows on an EFI/UEFI disk.
• 4. Receive error message: "Windows cannot be installed to this disk. The selected disk has an MBR partition table. On the EFI system, Windows can only be installed to GPT disks," as shown in the image below.

When you encounter any of the above-provided cases, you must change your disk from MBR to PGT.

Conclusion

This page uncovers two major solutions for successfully converting MBR to GPT disk without OS. However, which one is more suitable for me? Or, which method should I try?

Here is the EaseUS Editor's suggestion:

• If you prefer to clean all existing volumes on the old disk to change MBR to GPT without OS, CMD with DiskPart command lines can work. 
• To convert data or OS disk from MBR to GPT without data loss or OS boot issues, EaseUS Partition Master is the best choice. 

As for Windows beginners, we think Method 1 - EaseUS Partition Master, with its sophisticated disk conversion feature, is more friendly and efficient for you to try.

FAQs About MBR to GPT Conversion

Read on and check the answer to your question here now:

1. Is GPT or MBR better?

Here is a comparison table of MBR vs. GPT, from which you will learn which partition style you should use for your disk:

Conclusion: GPT Disk Exceeds MBR Disk in Many Aspects

According to the comparison table, it's clear that the GPT disk exceeds the MBR disk in many aspects, for example:

• Faster Boot Speed: GPT UEFI can load the operating system faster than traditional MBR BIOS boot mode.
• Better Operating System Compatibility: GPT has better OS compatibility than MBR as it supports most operating systems, including Windows Server and macOS.
• Advanced-Data Protection: GPT contains the backup of the primary GPT header and partition entries that protect data on the disk better.

In other words, if you need to install the latest operating system on your disk with a fast boot speed, GPT is better. GPT supports UEFI boot mode, which loads the operating system faster than the traditional BIOS mode on the MBR disk.

2. Should My SSD be MBR or GPT?

According to the MBR vs. GPT comparison table at the beginning of this page, we have reasons to believe that GPT is more suitable for an SSD disk.

GPT supports more than four primary partitions on SSD. It supports more than 2TB storage (compared to MBR). Also, it is more compatible with the newer UEFI-based systems.

3. What Happens If I Convert MBR to GPT?

Basically, converting MBR to GPT is highly dependent on which method you would like to use for MBR to GPT conversion.

If you use EaseUS Partition Master as recommended in Method 1 on this page, you'll see that only the partition style changes. Your data and partitions are all the same as before.

However, if you used Windows Disk Management or DiskPart to change MBR to GPT disk for free, three things will happen to your disk:

1. 1. Data loss;
2. 2. Partition loss;
3. 3. Partition style change: from MBR to GPT.