USB drive showing half capacity?

The other day something weird happened to my USB drive.

Here’s my story…

I have a capacious 64GB USB Drive.

It’s like sitting first class on Delta Airlines, sitting in the handicap bathroom stall at Old Navy or sitting in the front seat of a Hyundai Equus.

It’s big.

I purchased this thing when 64GB USB drives began flaunting their commodious features – so it wasn’t cheap.  And I’m proud of the space.My 64GB Cruiser Glide USB DriveSo, I wanted to install Mac OS X Yosemite in VirtualBox so I installed IESD, converted the .app to a .dmg and ran HDITUTIL to spruce up final product.

Once I finished my digital hocuspocus, I plugged my thumb drive into my Mac Mini but when I dropped the 32GB file onto the drive, my Mac bitched about there not being enough space on the destination drive.

I had to do a double take.  I knew my USB drive wasn’t damaged because it was just working a moment ago.

Low and behold, when I pressed Command + i and viewed the info, my Mac was only detecting 32GB of space.  In fact, it erroneously thought the maximum capacity of my 64GB drive was only 32GB.

Let’s just say I was bit peeved.

Flustered, I yanked the drive and roughly attached it to my PC.

Perhaps it’s a Mac thing right?

But Windows was showing the same problem.  I thought about reformating the volume; however, 32GB was the largest capacity visible from the drop down list.

I didn’t even have an option to format at 64GB!

64GB USB Drive showing half capacity

What the heck are you supposed to do when the Windows format tool won’t let you format your removable media at full capacity?

Diskpart will save your butt man

This is seriously a task for diskpart.exe.

It’s a built in Windows tool that lets you partition your disk.  In other words, it lets you divide up a physical disk into logical volumes.  You can also delete partitions.

It’s this last part, deleting partition, which saved my butt.

Here’s how this works:

Bust open a command prompt and type diskpart.  You can get here fast by pressing the Windows Logo key on your keyboard and the letters “xa”.

The first thing we need to do is list all the disks that Windows knows about.


list disk

diskpart.exe list diskFrom the graphic above, you can see diskpart knows my disk is 59GB.  So that’s a good sign.  It’s not showing up in the GUI though so we need to fix that.

Let’s select the disk number that represents our USB drive (just substitute the disk number with the respective one showing up on your screen):

select disk 1

and then select the partition. We want to select Partition 1 because it’s the only partition on the USB drive and we need to nuke it.

select partition 1

Select Disk and Partition

Now we need to delete this partition.

Now this part is crucial.

Make sure you are 100% certain you selected the right disk because there is no way to back out of this process.  Once we type delete partition all the data will instantly be obliterated.  There’s no confirmation or warning box.

Scary but true.

delete partition
Delete partition with diskpartNow we’ll create a shiny new full-size partition.

create partition primary

Great, now type:

list partition

We want to make sure that everything looks good.  You should see Partition 1 with the correct size under the Size column.

Now type exit to get out of diskpart because our dirty work is done!

Create partition primary with diskpart

If you right click your USB drive in File Explorer and choose format you’ll see the full capacity listed.  What a welcome change.

Formatting a USB DriveAnd that my friends is how to make your USB drive show full capacity again.


I like full capacity


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Posted in Hardware, Windows, Windows 7, Windows 8, Windows 8.1, Windows Vista, Windows XP Tagged with: , , ,
  • Stefan Kroon

    Thanks. This turned my 64gb flash drive from a 32gb flashdrive into a 0gb drive. down goes 40 bucks.

    • Brayan Talts

      You should try using gparted

  • stu anderson

    Awesome! Followed the instructions to the letter, fully regained this missing 32g Cheers bud!

  • Theodore Styron McLeod III

    woah. thanks this worked perfectly!

  • Drew McManus

    Terrific instructions, many thanks!

  • Amy Savvides Johnson

    Thank you so much. Downloaded Windows 10 and not only did it delete everything on it (ok, it didn’t tell me it would but I might have guessed!) but somehow lost half the capacity. This fixed it!

  • wimpendale

    One of the first results that showed up in google and exactly what I needed. Thanks for the walkthrough.

  • Sean Rowell

    Genius, saved my life

  • T1

    Below are steps I received from manufacturer in case this helps anyone – very similar to steps in this original article above I assume. My problem was a 64GB USB flash drive was showing just 32GB, and this was after I created a Recovery Drive on Windows 10 on the USB drive and later changed my mind and wanted to use the drive for something else. Just be very careful you follow the commands on the correct disk number as mentioned in the original article!!! I followed these commands below very carefully and it fixed my problem.

    “Usually this happens when you a backup program or image recovery maker tries to use the flash drive. Try the steps below and see if your problem is corrected. Please ensure your USB drive is plugged in while you do this process.

    1. search for command prompt (CMD)

    2. right click on Command Prompt(cmd.exe) & Click on Run as Administrator

    3. Type diskpart

    4. Type list disk (this will list the drives on the computer, be sure to notice which disk number the Flash drive is and make sure the space is correct, if it does not list the full space stop her or if you are not sure stop here)

    5. Type select disk X (replace X with the number that your computer assigned to your USB drive)

    6. Type clean (if there is an error stop here)

    7. Type create partition primary

    8. Type format fs=exfat quick

    9. Type active

    10. Type assign

    11. Type exit

    Now verify that your Product is working or not and that the space is correct.”

    • Ruan Venter

      Thanks this Helped me the best

    • Matěj K

      Thanks for help bro, this really work for me.

    • Dani Kaos

      Thanks a lot!

  • pinkmaro

    awesome great help! same cause as T1~ and YAY now i have my “64GB” back!

  • daddybdg

    Thanks mucho!

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  • RD

    Thank you very much. My EMTEC 64 USB flash drive has returned to 64GB again.

  • paulgj

    I had the same problem but I simply did a diskpart clean command and then let windows disk management take care of the partitioning

  • Thomas Jr

    Jesus christ, why can’t you go straight to the point you freaking w*h*ore. same problem happened to me, bought a 64 flash on amazon and got a 32Gb.

  • Scorp

    Worked perfectly Thanks for taking the time to do this.

  • Maxx Le

    you are the man! many thanks.

  • Madhu Krishna

    Help me please 🙁 anyone :'(

  • Madhu Krishna

    Thanks a million man…. you are my god 😀

  • André Bekkers (drédré)

    Wiindows X… 2016… needing Diskpart… .. . my gotte nazi’s
    I most likely used win USB tool to half my GB’s on Kingston drive.


  • Thomas Jr

    Thank you so much for this, worked beautifully.

  • Jordan

    Brilliaant. Thanks!

  • Cameron Taylor

    Please move yourself up the social ladder to GOD status. Many thanks

  • Judge Judy


  • Peter Cobrin

    You are a star!!!

  • Matthew

    THANK YOU!!!!!!!!!!!!!!!!! :DDDDDD

  • Sheila Garmon

    This was great step by step and screenshots along the way to look for. Wished the rest of the trouble shooting sites would be this precise, thank you bunches. I too was frusterated and about ready to scream or throw the drive being defaulty or a virus on there which I would not know or if that even happens…but again enough said YOU ROCK!!!

  • Lupf

    Thank you very much.

  • epp

    This did not work for me. I used a program to convert my 64GB micro SD to FAT32 and now it is stuck on 32GB. Tried everything including your steps and another program that is supposed to fix this. ARGH!

  • abhimanyu

    good one bro, keep it up.

  • Kaylem Joseph