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3TB Hard Drive Only Shows 2TB - How to Break 2TB Limit and Format 3TB HDD Windows 10

Updated by Cedric Grantham on Feb 23, 2021
Written by Cedric Grantham

Q: 3TB drive format Windows 10 not working, how to solve?

"I am using a Western Digital 3TB hard drive and I can not format the extra 700GBs. Once I hit format, it says " Windows can not format the drive ". I tried everything I could think of but it doesn't work either. Please help." - A user from Microsoft Community

3TB hard drive only showing 746GB/750GB on Windows 10, 3TB hard drive only shows 2TB, or 3TB HDD not showing full capacity issue happens to a lot of users. When you check the disk capacity in Disk Management, you might see the 3TB hard drive only showing as a 2TB partition. The remaining space is displayed as an unallocated space, but you cannot use it to expand or create new partitions.

3tb hard drive only shows 2tb

Why Does My 3TB Hard Drive Only Shows 2TB 

This happens mostly because your 3TB hard disk was initialized to MBR.

So, why 3TB hard drive only uses 2TB, and why you cannot create a new partition with the unallocated space on the 3TB disk? It is most likely because of MBR disk' limitation. If you check the partition style, you will find it is MBR (Master Boot Record), not GPT (GUID Partition Table).

We have a detailed guide to explain MBR VS GPT. Here, let's simply look at the difference between MBR and GPT disks, and then you'll see why the 3TB hard drive only shows 2TB.  

Comparison MBR GPT
Maximum partition size 2TB 9.4ZB
Maximum partition numbers 4 primary partitions or 3 primary partitions +1 extended partition (logical partitions are not limited) 128 primary partitions
Boot mode BIOS UEFI

Now, you know that, for a 3TB MBR hard drive, Windows will only be able to address the first 2 TB and all that extra storage beyond 2TB will be unusable. In this case, you can format the 3TB hard drive and use the full space by converting MBR to GPT. Move on, let's see how to convert MBR to GPT without data loss.

How to Fix 3TB Hard Drive Only Shows 2TB and Format 3TB Hard Drive on Windows 10/8/7

To solve the 3TB hard drive showing as 2TB problem and format a 3TB hard drive on Windows 10/8/7, you can convert the MBT disk to GPT disk in three ways below. The first method is the best choice as there is no need to delete partition or data at first. The second and third ways require partition deletion before the conversion.

1. Convert MBR to GPT Without Losing Data by Using a Partition Manager

The first way we strongly recommend you try is using EaseUS Partition Master - a superior disk management tool that can directly convert MBR to GPT without deleting any partition or file.

With EaseUS partition manager, you can:

  • Resize/move partitions (e.g., move space from D drive to C drive), create, format, delete, and merge partitions
  • Copy and clone an entire disk to another even the target partition is smaller than the source
  • Convert a logical partition to primary or primary partition to logical, FAT32 to NTFS partition, and more
  • Migrate OS to SSD to speed up Windows to upgrade hard disk and speed up Windows 10

Now, download EaseUS partition management tool to convert MBR to GPT with a few clicks. You can still easily convert GPT to MBR in vice versa.

Step 1. Download and launch EaseUS Partition Master on your Windows computer.

Step 2. Right-click the MBR disk that you want to convert and choose "Convert to GPT".

convert MBR to GPT - 1

Step 3. After that, find and click the "Execute 1 Operation" button on the toolbar and choose "Apply" to start the conversion. You need to restart your device to enable this change.

convert MBR to GPT - 2

2. Convert MBR to GPT to Format 3TB HDD in Disk Management

Windows Disk Management offers the disk conversion feature. But it only converts an empty disk or you will see the Convert to GPT Disk greyed out. If there are files or partitions on the 3TB hard drive, back up all the data beforehand.

Step 1. Right-click on the Windows button, select "Disk Management".

Step 2. Right-click the 3TB hard drive shows the wrong capacity. Choose "Delete Volume...". 

Step 3. When the hard drive shows as unallocated space, right-click the disk and choose "Convert to GPT Disk".

Convert MBR to GPT in Disk Management

3. Convert 3TB Disk from MBR to GPT Using Diskpart in CMD

You can use the Command Prompt to convert MBR to a GPT disk. Also, you need to delete all the files and partitions. So, restore important data in advance. 

Step 1. Press Win+R keys, type CMD, and press Enter to open the command prompt.

Step 2. Type diskpart and hit Enter. Type the following commands in order; remember to press Enter after you input each one.

list disk
select disk n
(n means the drive letter, replace it with your 3TB drive letter)
clean (clear all partitions on the selected disk)
convert gpt

Step 3. Type Exit when the conversion finished. Now, the 3TB hard drive becomes all unallocated. You can continue to format the 3TB disk and create partitions. Type the following commands and press enter after each one. 

create partition primary 
assign letter=N (N can be replaced by any letter that is not occupied currently) 
format fs=ntfs quick 

Step 4. Type exit and press Enter.

Final Verdict

After reading this post, we're sure you've understood why you can't format a 3TB hard drive on Windows 10. You can break MBR 2TB file system limit and convert your disk to GPT. Thus, you can format a 3TB hard drive and take full use of the space.

EaseUS Partition Master is a user-friendly partitioning tool that allows both beginners and pros to partition 3TB, 4TB, as well other large-capacity disks. It can easily optimize disk partitions to extend your hard drive and computer's capableness.  

More 3TB HDD FAQs That You Might Be Interested in  

Here are a few questions related to why the hard drive not showing full capacity and how to format a 3TB HDD on Windows 10. If you also have any of these problems, you can find the methods here.

Does Windows 10 support 3TB hard drives? 

Windows 10 supports large disk capacities, such as 2TB, 3TB, 4TB, and 6TB. For a hard drive that is larger than 2TB, you need to initialize it to GPT or convert it to GPT (when data have been saved).

Why is my hard drive not showing full capacity?

Except for the wrong partition table, the hard drive might show the wrong capacity for other causes:

  • The hard drive driver is out of date.
  • The hard drive is format improperly or the formatting process is incomplete.
  • MBR or GPT header gets corrupted due to accidental insertion and removal.
  • Errors caused by bad sectors.  

How do I format a 3TB hard drive to FAT32? 

FAT32 can only support up to 2TB partition size, and a single file can only support up to 4GB. This means you can't use another 1 terabyte space if you format a 3TB hard drive to FAT32. But if your disk is a special 4K sector disk, FAT32 can support up to 8TB of capacity.

If you insist on formatting your 3TB disk to FAT32, follow these steps:

  • Install and launch EaseUS Partition Master. Right-click on the 3TB hard drive and choose "Resize/Move".
  • Drag the partition ends to make the partition less than 2TB. 
  • Right-click on unallocated space, and choose "Create" a FAT32 partition.

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Updated by Cedric Grantham

Cedric Grantham is one of the senior editors of EaseUS who lives and works in Chengdu, China. He mainly writes articles about data recovery tutorials on PC and Mac and how-to tips for partition management. He always keeps an eye on new releases and likes various electronic products.

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  • I love that the changes you make with EaseUS Partition Master Free aren't immediately applied to the disks. It makes it way easier to play out what will happen after you've made all the changes. I also think the overall look and feel of EaseUS Partition Master Free makes whatever you're doing with your computer's partitions easy.

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  • Partition Master Free can Resize, Move, Merge, Migrate, and Copy disks or partitions; convert to local, change label, defragment, check and explore partition; and much more. A premium upgrade adds free tech support and the ability to resize dynamic volumes.

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