How can I restore USB drive back to full capacity in Windows 11/10?

The missing space is the one without a partition. You can create a new partition for the allocated space. This will help you restore usb drive back to full capacity.

Sometimes, what looks like a 256GB drive is actually a fake with a much smaller capacity. Restoring it to full size doesn’t actually give you more space—it just tricks your system into thinking it has more. So, if your drive is fake, trying to restore full capacity won’t actually help, and you’re just wasting time. Forcefully repartitioning or reformatting a drive can sometimes cause damage, especially if the drive is already faulty or fake. It might stop working altogether or become unreliable.

If you mess with the drive or try to alter its capacity, it might void any warranty or support options from the manufacturer. Restoring USB drive back to original full capacity size or faulty USB can lead to slow speeds or crashes. The drive might seem full but perform poorly because it’s not genuinely the size it claims to be.

My advice about restoring USB drive back to original full capacity size: double-check if the drive is genuine first. If it’s fake, restoring capacity isn’t going to fix the actual problem—it’s just a scam. If it’s legit, then go ahead but do it carefully, and always back up your data first. Better safe than sorry!

Restoring USB drive to full capacity in Windows 11 by deleting partitions and formatting it is generally safe — as long as you’re careful and make sure you’re working on the right drive. 

Here’s the deal:  

• When you restoring USB drive to full capacity in Windows 11. If you accidentally pick the wrong drive in Disk Management or Diskpart, you could wipe out your main hard drive or another important drive. That’s a big no-no.
• Always double-check the drive size and label before hitting delete or clean.
• Make sure you’ve backed up any important data first — because this process erases everything on the USB.

In my experience:  

• It’s pretty straightforward, and most of the time, it works without issues.
• Sometimes, if the drive has hardware problems or bad sectors, formatting might not fix everything, and the drive might still be unreliable.
• If your drive was previously partitioned or had a corrupted filesystem, this method is actually a good way to fix it.

File Explorer in Windows does show the free space available on a USB drive — but it only shows this within the currently formatted partition.

✅ What You See in File Explorer

When you plug in a USB drive and open File Explorer, it shows:

• Used space
• Free space
• Total capacity (of the current partition only)

You can view this by:

Right-clicking the USB drive in File Explorer > Properties.

❗ What It Doesn't Show

File Explorer won't show:

• Unallocated space (space not part of any partition)
• Hidden partitions
• Multiple partitions on removable USB drives (Windows usually shows only the first partition)

To see the full physical size of the USB drive, including unallocated or hidden space, you must use Disk Management or a third-party partition tool. They can restore restore USB drive back to full capacity by merging or creating new partition on unallocated free space.

If the USB is not showing the full capacity in Windows 11/10, then here are a few suggestions to help you restore USB drive back to full capacity in Windows 11/10. Please doing that, kindly backup the important for unexpected error.

First, Check the Full Disk Layout

1. Press Win + X > select Disk Management
2. Locate your USB drive in the lower section
3. See if there's unallocated space or multiple partitions

Second, Reformat the Drive (if no important data)

diskpart
list disk
select disk X   (replace X with your USB disk number)
clean
create partition primary
format fs=exfat quick
assign
exit

Third, Test for Fake USB

Use a tool like:

• H2testw (Windows)
• FakeFlashTest

These tools write and verify data to detect if the USB is truly 256GB or a fake.

If tools reveal the USB is fake (real capacity is 32GB), there's no fix available to increase the USB storage. The only solution is to replace the drive and possibly report the seller.

Why does the 256GB flash drive only showing 32GB in Windows file explorer? For Windows 11 and Windows 10 OS, it's likely due to one of the following reasons:

Drive formatted with FAT32

FAT32 has a size limitation of 32GB when formatted using Windows tools, even though the file system supports up to 2TB. Some formatting utilities will cap it at 32GB.

Hidden or unallocated space

The drive may have remaining space that's not allocated or hidden, which doesn’t appear in File Explorer.

Drive was partitioned incorrectly

Some tools or OS installations may have created a small partition and left the rest unallocated.

Fake USB drive (counterfeit)

Sadly, some low-quality or counterfeit drives report a higher capacity than they actually have. These often show 256GB but only have 32GB of real storage.

You need an advanced disk partition tool in order to restore USB drive back to full capacity in Windows 11.