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How to Wipe a SanDisk USB & Reformat It to Its Full Capacity

The capacity of my 256 GB SanDisk USB drive initially was 256 GB. I reformatted it to ExFAT and its capacity is still 256 GB. I initially created it to be a bootable drive. Now, instead of having the full capacity of the USB, I only get a 6 GB. So, I tried to erase the whole USB drive in Disk Utility but it does not work. It still shows the capacity of 6 GB. The partition icon is greyed and I can't use it. How can I get back the whole initial capacity of my USB drive?

Best Answered by

iBoysoft author Connie Yang

Connie Yang

Answered on Monday, April 29, 2024

It seems that your Disk Utility only shows the volumes of the USB drive, so you mistakenly reformat a volume rather than the entire USB drive.

You need to click the View button on the top toolbar of the Disk Utility window. Then, select Show All Devices to let the entire physical SanDisk USB be displayed on the left sidebar of the Disk Utility window.

After that, you can get down to formatting your USB on your Mac. Select the top level under the External section to choose the whole USB and click Erase. On the pop-up, name the USB, choose exFAT as the format, and then select GUID Partition Map as the scheme. Finally, click Erase to start reformatting.

Then, you can get a USB with its full 256 GB capacity.

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