By AOMEI / Last Updated February 20, 2020

My cloned hard drive shows wrong size, why?

When you upgrade to a larger hard disk drive (HDD) or solid-state drive (SSD) by cloning the old drive, you may find the cloned hard drive has the same disk space as the original drive. In other words, the cloned drive not showing full capacity.

This is because when you clone the hard drive, you also cloned the partition size besides the data. When the cloned drive is larger than the original drive, most of the cloning programs, if not all, will leave the extra space on the cloned disk as unallocated space. And then you will meet the HDD/SSD shows wrong capacity issue.

In Windows File Explorer, you cannot see the unallocated space. That is why some users say they have lost disk space after cloning hard drive. You can open Disk Management to see if there is unallocated space on your cloned hard drive.

How to fix cloned hard drive shows wrong size?

There are two workaround solutions to fix the HDD/SSD shows wrong capacity. If you have finished cloning the hard drive, you can go to Disk Management to handle unallocated space. Or if you prefer a quick fix once for all, you can perform a clone via one professional cloning software that can help you clone to larger drive without causing disk capacity loss.

Part 1. How to use full capacity of hard drive

You can add the unallocated space on the cloned hard drive to the contiguous partition with Disk Management or DiskPart.exe. you can follow the steps below to use Disk Management to handle unallocated space after cloning.

1. Press Windows + R key and press enter. In the Run window, type “diskmgmt.msc” and press Enter to open Disk Management in Windows 10/8/7.

2. In Disk Management, right-click on the partition before the unallocated space, and select Extend Volume. If the partition and the unallocated space are not contiguous, the option Extend Volume is greyed out.

3. Follow the Extend Volume Wizard to add unallocated space to this partition.

Besides extending volume, you can also use the unallocated space to create one or more new partitions.

If you can neither use the unallocated space to extend the adjacent partition nor create a new partition, then your cloned hard drive is larger than 2TB and it is MBR partition style. On MBR disk, disk space beyond 2TB will become unusable.

In this case, you can't use full HDD capacity after cloning unless you convert it to GPT disk. Converting a disk to GPT from MBR with Disk Management requires you to delete all the partitions on this hard drive. Then the time you spent on cloning hard drive is for nothing.

Or if you want a way to prevent cloned hard drive with unallocated space in the first place? Keep reading to learn more.

Part 2. How to avoid cloned hard drive shows wrong size

Choose the right cloning software

The key to cloning a hard drive of different size without leaving unallocated space is to choose the proper cloning software. There is a free hard disk cloning software called AOMEI Backupper Standard that can help you clone hard drive to a larger one without causing disk capacity loss.

  • For cloning to a much larger HDD or SSD, AOMEI Backupper gives you three options to manage the partition size. You can manually edit the partition size on the clone disk, let the program automatically adjust the partition size to fit up the entire hard drive, or clone without resizing partitions

  • When cloning MBR disk to GPT disk larger than 2TB, you will not lose disk space beyond 2TB because the program takes care of it. The cloned hard drive can still be used as GPT disk and remains bootable.

  • When you upgrade to an SSD, it provides an option to align partition to optimize for SSD. What’s more, it will not interrupt your work while cloning because of the volume shadow copy service (VSS) technology.

Cloning process step by step guide

AOMEI Backupper provides an intuitive interface, all operations with AOMEI Backupper become quite easy. To upgrade to a larger hard drive, you can follow the steps below.

1. Install this program on your computer, and open it.

2. Select “Disk Clone” under "Clone" tab.

Disk Clone

3. Click on the smaller SSD to select it as the source disk, and click on "Next". Then click on the larger SSD to set it as the destination disk, and click “Next”.

Select Disk

4. Check the option “SSD Alignment”, which is important for keeping the SSD at its best performance. Then click “Start Clone” to confirm.

Start Clone

In this way, a cloned hard drive will not show wrong size no matter how larger your destination disk is.

Tips: Click on the option “Edit Partitions”. By default, it is set to copy without resizing partitions, which is often used for cloning to a disk with the same size as the original one. It is recommended to select the option “Add unused space to all partitions” here because you are cloning to a larger drive.

    Add Unused Space

Note: You can upgrade to higher version to use "manually adjust partition size" or "Add unused space to all partitions", or clone system disk between MBR and GPT.

Also, you still can clone HDD to smaller SSD with the same steps above. Besides the Clone feature, AOMEI Backupper has excellent backup and restore features, so users can use it to backup operating system, and restore to the new SSD when your computer has only one SSD slot.


That’s all for how to fix the cloned hard drive shows wrong size problem. You can go to Disk Management to add unallocated space. Or you can simply perform the hard drive clone with AOMEI Backupper Standard, it’s possible to manage the partition size to suit your new hard drive.