For Apple Mac users, the easier way to format USB flash drive to FAT32 is using the Disk Utility. Formatting would erase data completely, make sure that you have a data backup.
To format a USB Flash Drive to FAT32 in macOS follow these steps.
Step 1 - Connect the USB
Connect the USB Fash Drive to the macOS computer.
Step 2 - Open Disk Utility
Go to Applications > Utilities > Double click and open Disk Utility.
Step 3 - Identify the USB
Select the USB Fash Drive you want to format and click Erase button.
Step 4 - Set up the name
Enter the new name for the USB Fash Drive (OPTIONAL).
Step 5 - Select partition type
Select MS-DOS(FAT) for Format.
Step 6 - Select MBR
Select Master Boot Record for Scheme.
Step 7 - Start the format
Click the "Erase" button.
Step 8 - Check the result
Depending on the USB Drive size, the operation might take some time.
Congratulations, now you are ready to use the USB Flash Drive.