Format a Drive for Mac & PC Compatibility

This post will teach you how to format an external hard drive or a USB flash disk so it can be used on both Mac and Windows PC.

If you have an external hard drive or USB flash drive that you’d like to use on both Macs and Windows PCs, choosing the right file system to format the drive can be confusing. Learn a few ways to make your drive Mac and PC friendly.

Need to access or transfer files between Mac and PC? As simple as this task sounds, it’s not very straightforward for inexperienced users. Since Mac OS X and Windows use totally different file systems, the way a drive is formatted can determine what type of computer it will work with. In fact, there are four ways you can format an external or USB flash drive to achieve varying degrees of compatibility between Macs and PCs. Let’s take a look at them:

HFS+

Mac OS X’s native file system is HFS+ (also known as Mac OS Extended), and it’s the only one that works with Time Machine. But while HFS+ is the best way to format drives for use on Macs, Windows does not support it. If you’re only going to be using your external or USB flash drive with certain PCs – such as at home or the office – you might be interested in a program called MacDrive. When you install MacDrive on a Windows PC, it will be able to seamlessly read & write to HFS+ drives. This isn’t a good solution if you need your drive to work on any PC without installing software, though.

NTFS

The native Windows file system is NTFS, which is only partially compatible with Mac OS X. Macs can read files on NTFS drives, but it cannot write to them. So if you need to get files from a PC to your Mac, NTFS is a decent option. However, you won’t be able to move files in the other direction, from Mac to PC.

FAT32

The most universally supported way to format your drive is with the FAT32 file system. It works with all versions of Mac OS X and Windows. Case closed, right? Well, not so fast. Unfortunately, FAT32 is a very old file system and has some technical limitations. For example, you cannot save files that are larger than 4GB on a FAT32-formatted drive. This is a deal-breaker if you work with huge files. The other limitation is the total size of the partition. If you format your FAT32 drive in Windows, the drive partition cannot be larger than 32GB. If you format it from a Mac running 10.7 Lion, the drive partition can be up to 2TB. Much better, except for that pesky 4GB limit.

exFAT

The exFAT file system eliminates the two major deficiencies of FAT32: the largest partition and file sizes it supports are virtually unlimited by today’s standards. Awesome, it’s perfect! Almost… since exFAT is fairly new, it isn’t compatible with older Macs and PCs. Any Mac running 10.6.5 (Snow Leopard) or 10.7 (Lion) supports exFAT, while PCs running Windows XP SP3, Windows Vista SP1, and Windows 7 are compatible. If you know you’ll be using computers running updated versions of these operating systems, exFAT is the clear best choice.

Important note: formatting a drive deletes permanently all data stored in it. You should make a copy of your drive’s data on your computer before proceeding.

Format a drive using Disk Utility on a Mac:

Step 1: Open Disk Utility on your Mac. You can quickly search for it in Spotlight Search or find it within the /Applications/Utilities folder.

Step 2: Connect your external hard drive to the Mac. If you Mac recognize the hard drive, its name will appear on the left sidebar under External.

Step 3: Click the drive name, then click Erase. Click the pulldown menu alongside Format and select MS-DOS (FAT32) or ExFAT.

Step 4: Click the Erase button to start formatting the drive for Mac & PC.

After formatting, your drive will be compatible to work with both Mac and Windows PC.

Format a drive using Windows:

Step 1: Plug in the drive and open Windows File Explorer.

Step 2: Go to This PC (aka Computer or My Computer).

Step 3: Find the drive and right-click on it, select Format…

Step 4: Click the drop-down menu beneath File system, and select your file system of choice (FAT or ExFAT).

Step 5: There is a checkbox for Quick Format under Format options. If you uncheck it, the computer performs a normal format – files are removed and the drive is scanned for bad sectors. If it’s checked, only the files are removed and no scan is performed.

Step 6: Click Start then OK to confirm that you want to format the drive.