How Do I Reformat an SD Card?

by C. Taylor

Windows, as well as many peripheral devices, include formatting utilities that can reformat your Secure Digital card. Reformatting not only erases all data on the SD card, but it also specifies the file system used, such as the FAT32, exFAT or NTFS file systems. When reformatting in Windows, you also have the option to overwrite data and establish a drive label for easier identification on your system.

Formatting with Peripheral Devices

If you plan to use the SD card exclusively in a peripheral device, such as a digital camera, you should use the device's integrated formatting utility. Doing so ensures the SD card is properly formatted for the device and creates any required files or folders.This procedure differs for each device, so you need to consult your device's manual for detailed instructions.

Accessing the Card on a Computer

Formatting the card on a computer requires a card reader. Many modern computers have an integrated card reader that supports SD cards. However, if your computer does not have a card reader, you can purchase a USB card reader. Some types of SD cards, such as microSD cards, are not readable by all card readers, but you can purchase an SD card adapter to convert the microSD card to a standard SD size.

Windows 7

Windows 7 contains two utilities for formatting your SD card: Disk Management and Windows Explorer. Disk Management is found by typing "disk management" in the Start menu's search bar and pressing "Enter." Its formatting utility is launched by right-clicking the SD card and selecting "Format." Windows Explorer is found by clicking "Start," then "Computer." Likewise, right-clicking the SD card and select "Format" launches the formatting utility. Both utilities let you change the file format and label the card. Unselecting "Quick Format" overwrites any data during the reformatting procedure, but it takes longer.

File System

The biggest consideration when reformatting your SD card is the file system you wish to use. If you're formatting the SD card in a peripheral device, this isn't an option; the device chooses the best format. However, in Windows 7, you need to choose between NTFS and one of the FAT systems. If the SD card will only be used within Windows, NTFS is the best choice. For compatibility between Windows, peripheral devices and Mac computers, use FAT or FAT32. If the card capacity is 64GB or greater, use exFAT. Doing so maintains compatibility with Windows and Mac computers, but you lose peripheral device compatibility. However, exFAT does not suffer the same 4GB file size limit of the FAT32 system.