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For example, if you own a SanDisk micro SD card, you should have a micro SD card adapter that came with it. The adapter looks like a regular SD card with a slot at the bottom where you insert your micro SD card. Note that most Micro SD cards that are 32 GB or less come formatted as FAT32. Cards above 64 GB are formatted to exFAT file system. If you are formatting your SD for your Android phone or Nintendo DS or 3DS, you will have to format to FAT32. With Android, many of your apps or custom recoveries, if you are rooted, will not read exFAT. Formatting to FAT32 is usually your best option, however, FAT32 formatted cards won't let you transfer or store a file more than 4 GB. You can also purchase a third-party micro SD card adapter if you don't already have one. Just make sure that it is compatible with your micro SD card. Some third-party adapters also use a USB component on one end and operate like a flash drive. Depending on your computer and type of adapter you will either need to use your SD card slot or a USB port. If you are using a micro SD card adapter, make sure that the lock toggle is up and in the unlocked position. If it is in the locked position your computer may not read the card or let you make any changes. It may be "Read only". It's a good idea to copy the files currently on the card over to your computer to save. This will allow you to keep your data and files for transferring back after you format. This method works for Windows 7 and up. Once you are in your "Computer" window a list of all your computer drives will display on-screen. Locate your micro SD card. It can be identified by the brand name of your SD card unless you changed the name of your card. If you changed the name, locate it by that name. A window displaying formatting options will display on-screen. If you don't see a "Format" option you may have to download and install the fat32format utility in GUI version. If you were able to click the "Format" option, a box will appear with several options including "Quick Format". Check that box for best results. If you had to install the fat32utility, you will also see the same box pop up once you have launched the guiformat.exe file. Before you click "Start" make sure that the other tabs and options are correct. Check that the "Capacity" has the right amount of storage. Make sure you are formatting to the desired format, usually FAT32. Your computer will begin to format your micro SD card, and erase all its contents. Once formatting is complete you will have a blank, newly formatted micro SD card for use.
Insert your micro SD card into a micro SD card adapter or reader compatible with your micro SD card. Insert the card reader or adapter into a USB port or SD card slot on your Windows computer. Click on the Start menu and select "Computer" or "My Computer". Right-click on your card reader in the list of drives and select "Format". Place a checkmark next to "Quick Format". Click on the "Start" button.