How to Change BIOS Mode from Legacy to UEFI Without Reinstalling Windows 10

We’ll do it in just two commands

Microsoft added a useful tool missing from the earlier versions of Windows and even some older versions of Windows 10. TheMBR2GPTtool enables Windows 10 users to convert Legacy BIOS to UEFI without reinstalling Windows 10.

You can invoke the MBR2GPT tool using Command Prompt, and two commands later, you’ll have switched from Legacy BIOS to UEFI.

Which Is Better: Legacy BIOS vs. UEFI

BIOS (Basic Input/Output System) is a piece of code that your microprocessor requires to start up after you press the computer’s power button. BIOS first appeared long ago and worked perfectly well. BIOS did have some constraints though.

For instance, BIOS uses Master Boot Record (MBR) to define a maximum partition capacity of 2.2 TB. Hardware developments over the past decade and a half warranted a new firmware. Then came UEFI (Unified Extensible Firmware Interface).

UEFI, much like BIOS, is low-level software that your computer runs when you press the power button and before booting the OS. UEFI is more robust and removes constraints associated with BIOS.

For instance, UEFI supports partitions of up to 9 ZB, offers faster boot time, and provides security features like “Secure Boot.”

Getting Ready to Convert Legacy BIOS to UEFI

You need to get a few things in order before we talk about changing BIOS from Legacy to UEFI.

Verify that you’re currently using Legacy BIOS. You don’t want to have to go through the entire process only to find out you were using UEFI the whole time.

Open the Disk Management app to verify which BIOS version you’re running. Search forCreate and format hard disk partitionsin the Start Menu and open theBest match. This will take you to the Disk Management app.

In the app, right-click on the disk on which you’ve installed Windows and selectProperties.

Next, you want to check your disk partition style to confirm whether you’re running the Legacy BIOS or UEFI. If you’re using BIOS, your disk partition style will be MBR. If you’re already on UEFI, the disk partition style will be GPT.

You can check the disk partition style under theVolumestab in Properties. Search forPartition styleunderDisk information.

The MBR2GPT tool is available on Windows 10 version 1703 and later. Verify that you have the right version before starting the process by searching forwinverin the Start Menu and opening the Best match. The new window that opens will display the version in the second line.

Assuming you’ve verified that you’re using the Legacy BIOS, there are a few other things you need to check, and in some cases, change.

How to Change BIOS from Legacy to UEFI

Once you’ve made sure everything is in order, it’s time to use the MBR2GPT tool.

mbr2gpt /validate /disk:0 /allowFullOS

If the disk you want to convert is not disk 0, replace 0 with the appropriate disk number.

If your disk doesn’t meet the conversion requirements, you’ll see an error. For instance, the following error resulted from validating a USB drive.

mbr2gpt /convert /disk:0 /allowFullOS

Let the conversion run, it should only take a few seconds.

Enjoy Your Modernized BIOS

UEFI comes with a lot of capabilities. Given that most modern systems are using UEFI, it’s only natural to want to convert Legacy BIOS to UEFI. Well, you’re all done. Fortunately, you didn’t have to reinstall Windows either.

Arjun is a freelance writer based in India. After working as an equity research analyst, Arjun decided to do something that he has been passionate about – tech. He gets excited talking about and explaining how to solve everyday tech problems. His area of expertise is Windows and is a go-to for all things Excel.Read Arjun’s Full Bio

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How to Change BIOS Mode from Legacy to UEFI Without Reinstalling Windows 10#

Which Is Better: Legacy BIOS vs. UEFI#

Getting Ready to Convert Legacy BIOS to UEFI#

How to Change BIOS from Legacy to UEFI#

Enjoy Your Modernized BIOS#