![](https://help.apple.com/assets/61E886D6F626695C732DB165/61E886D7F626695C732DB16C/en_US/f77bef81794f5b467f75cbe202ec7a2c.png)
Format a disk for Windows computers in Disk Utility on Mac
In Disk Utility, you can format an external disk that you can use with both a Microsoft Windows-based computer and a Mac. For example, you might want to do this if you use a flash drive to store data files you need to use on your Mac at home and when using a Windows-based computer at school or the public library.
WARNING: Formatting a disk or volume erases all the files on it. Save any files you need to another volume before formatting.
![The Erase dialog showing the name, format, and scheme fields.](https://help.apple.com/assets/61E886D6F626695C732DB165/61E886D7F626695C732DB16C/en_US/79437221b5bb0e159a3dc886f141d59b.png)
In the Disk Utility app
on your Mac, choose View > Show All Devices.
If Disk Utility isn’t open, click the Launchpad icon
in the Dock, type Disk Utility in the Search field, then click the Disk Utility icon
.
In the sidebar, select the disk you want to format to use with Windows computers.
Click the Erase button
in the toolbar.
In the Erase dialog, click the Scheme pop-up menu, then choose a partition scheme.
Click the Format pop-up menu, then choose one of the following:
MS-DOS (FAT): Choose this format if the size of the disk is 32 GB or less.
ExFAT: Choose this format if the size of the disk is over 32 GB.
Enter a name for the volume.
The maximum length for the volume name is 11 characters.
Click Erase, then click Done.