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Reformat your USB flash drive to access its full storage capacity

Reformat your USB flash drive to access its full storage capacity

Reclaim lost storage space by getting rid of the hidden files and junk that accumulates on your USB flash drive over time.

Nearly everyone has a USB flash drive for portable data storage nowadays, and for the most part they work with almost any computer effortlessly. Sometimes, though, a particular brand or model will not play nice when you frequently connect it to both Windows and Mac systems. Both operating systems routinely create hidden files, and items you thought you deleted may still be there after all. After a while you might not be able to take full advantage of your flash drive’s full capacity, because these unwanted files are taking up space.

For example, if I have a 4GB drive and I only have about 1.5GB of usable data on it, I might only have about 750MB of free space left. Of course, this doesn’t quite add up to my flash drive’s full size so clearly something I can’t see is there taking up space.

The first and most common way to fix this problem is to ensure your Trash has been emptied in Mac OS X. When you delete a file from your USB flash drive on a Mac, it goes to a special hidden directory on the drive and stays there until you empty the Trash. You must do this while your storage device is connected.

If the previous method doesn’t help you, the next one certainly will. Follow these steps to erase and reformat your drive:

1.) If you have any important data on your USB flash drive, make sure you temporarily copy the files to your Mac’s desktop.

2.) Open up Disk Utility (Applications > Utilities) and select your flash drive on the list to the left.

Reformat your USB flash drive to access its full storage capacity

3.) Choose the Erase tab near the top of the window and select MS-DOS (FAT) from the Volume Format drop-down menu. This is required if you want your drive to be Windows-compatible.

4.) Give your drive a name (keep it short with no special characters).

5.) Finally, press the Erase… button and your drive will be wiped clean.

This process will give you access to your USB flash drive’s full formatted storage capacity. If you backed up the drive’s data to your desktop, you can copy it back and use it just like before — with more free space!

136 Comments Have Been Posted (Leave Your Response)

Thank you so much!!

Thank you very helpful

This was the most helpful and simplest page I could find! It worked perfectly and saved me from having a lot of trouble in a photography class. Thank you so much!

Thank you so much!!!! I’ve been looking for ways to clean out my USB drive and this method has been the best.

You are the man!!!! Yahooo..brought back 25gigs by the trashing method!!!

I tried so many other things before I found this and it worked perfectly! Thank you SO much!

So simple I never would have thought of this. MANY THANKS!

THANK YOU SOOOOOO MUCH… I was literally about to shoot myself!

I didn’t think that deleting your trash thing would work but it does! THANKYOU!!! My 5 year old USB had only 436 MB out of 4 GB

How can i get rid of the name for example yours says 3.9 GB JetFlash. is there a way to get rid of this?

Well…I’m trying to download a mod for gta 5 online with my macbook and it said zero kb left I will try this when I wake up and tell you if it works!

my pendrive shows 0 bytes storage capacity how i recover it , i do all possible solution for my pendrive but i can’t get my storage capacity.

Thanks man! this is very helpful

Thank you so much. Trash bin emptying worked!!!!!

Thank you so much, you’re a lifesaver…I had a whole stack of flash drives I thought were unusable!

How Can i Downlaod this?

My 32GB USB had about 2GB left for some reason, even though it looked empty to me, but apparently it wasn’t! I did this and thank god I have all my space back! Now I can keep more backup files on it! Yay!!!

I have tried this and find that when I get to the ‘erase’ stage everything is ‘greyed out’ the files saved on the ESB have all become ‘read only’ and won’t let me delete or erase them, suggestions please :)

Robert Woznicki
March 7th, 2016, 9:23 AM

This don’t help me any. I have a 2G USB drive & only have 1.9G left. I also have a USB drive that I don’t know how many Gigabytes I had on it, but I have 7.5G left. I’m also using Windows- NOT A MAC!

thank you…very helpful

Thanks so much. I was unable to copy files from My Macbook Air to usb and from usb to my Macbook Air after following this process and restore my usb now i can do it

Thanks so Much!

Thank you this fixed my problem in no time!

hello. i am trying to update my pioneer head unit. the flash drive must be COMPLETELY empty, including the manufactured installed stuff, how do i do this? Can i do this? pretty stupid that pioneer just doesn’t sell it in a stick, i would buy it, this is driving me nuts

That was awesome and best of easy! Instructions so easy to follow and the clean up was finished in just a few minutes! Thanks for the help.

THANK YOU SOOO MUCH! this really really helped me out in a matter of seconds! Thank you!

Thank you SO MUCH!!!!

Thank you for those clear and helpful instructions.

the volume format option does not let me click ,it is silvered coloured ;so i can not format my usb drive by this process

I have tried everything that I can….pretty much it all says to do the same thing for Mac users…..Upon inserting,it says “the disk you inserted was not readable by this computer,the ignore or eject.I ignore and do the erase thing.I have tried to erase,and it says it has failed,cannot open device.HELP!!!

Don’t understand why this works but it does. Thanks a bunch!!

I have two 512GB USB’s that I bought off amazon and using this method I was able to make them both into a 540GB USB’s. That’s more than 50GB’s of more storage space. THanks a ton.

I’m using OS X El Capitan, and the Other storage ate up my storage

Thank you so much!

Thank you so much! this worked and was so easy to do for someone who is not tech-savvy like myself

Thanks a lot !! it worked perfectly