Format a SD Card / USB Flash memory in Disk Utility on MacUpdated a year ago
See instructions below on how to format a SD card or USB flash device. We recommend using FAT32.
In Disk Utility on your Mac, you can format an external disk for a Windows computer.
WARNING: Formatting a disk or volume erases all the files on it. Save any files you need to another volume before formatting.
In the Disk Utility app
on your Mac, choose View > Show All Devices.
In the sidebar, select the disk you want to format to use with Windows computers.
Click the Erase button
.Click the Scheme pop-up menu, then choose Master Boot Record.
Click the Format pop-up menu, then choose one of the following:
MS-DOS (FAT32)
Enter a name for the volume.
The maximum length for the volume name is 11 characters.
Click Erase, then click Done.