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Castiellm's avatar
Castiellm
Iron Contributor
Dec 11, 2025

How to change or convert mbr to gpt without data loss?

I want to install Windows 11 on my Windows 10 PC, which has a MBR partition. When I tried to install Windows 11, the setup wizard tells me only GPT partition table is supported. The built in disk man...
FinleyGrove's avatar
FinleyGrove
Iron Contributor
Dec 11, 2025

Converting MBR to GPT without data loss is possible using specialized tools designed for this purpose. Here are your options:

Use MBR2GPT Tool (Built-in Windows Utility)
Windows 10 and Windows 11 include the MBR2GPT utility, which can convert MBR to GPT without data loss.

Important: Your system must meet certain requirements:

  • The disk should have no more than 3 partitions (excluding the EFI system partition and recovery partitions).
  • You should have a UEFI firmware (not BIOS).
  • The disk should be healthy and free of errors.

 

Steps to use MBR2GPT:
1. Backup your data: Always recommended before making disk modifications.
2. Open Command Prompt as Administrator.
3. Run the validation command:

mbr2gpt /validate /disk:<disknumber> /allowFullOS

Replace <disknumber> with your disk number (you can find it in Disk Management).

4. If validation passes, proceed with conversion:

mbr2gpt /convert /disk:<disknumber> /allowFullOS

5. After you convert MBR to GPT, you need to change your firmware settings from Legacy BIOS to UEFI in the BIOS/UEFI firmware settings.

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