There are a few key reasons why exFAT drives are not readable on Mac by default:
Mac doesn’t include exFAT support natively
The exFAT file system was introduced by Microsoft in 2006 and was added to Windows Vista and later versions of Windows. However, Apple did not include native support for exFAT in Mac OS until 2012 with OS X 10.6.5 and later.
Without the appropriate driver installed, Mac operating systems earlier than 10.6.5 will be unable to mount and read exFAT formatted drives. This means if you format an external drive with exFAT on a Windows PC then try to use it on an older unsupported Mac, the drive will not show up at all or show up as unreadable.
Licensing and proprietary issues
Part of the delay in adding exFAT support to Mac was related to licensing issues between Microsoft and Apple over the proprietary exFAT file system. Microsoft owns patents and licenses exFAT commercially, whereas Apple’s HFS+ and APFS file systems are proprietary to Apple.
This meant Apple had to negotiate with Microsoft to license exFAT before adding official support in Mac OS. Licensing fees and terms delayed the adoption of exFAT reading abilities for earlier versions of Mac OS.
Designed for Windows first
Since exFAT was designed and introduced by Microsoft, it was engineered to be fully compatible with and optimized for Windows systems first and foremost. The initial priority and compatibility was for Windows Vista and later Windows versions.
Adding support for other operating systems like macOS came later down the line. The delayed additional of exFAT support to Mac OS was in part because Microsoft prioritized Windows compatibility over Mac in the early days of exFAT development.
Greater need for Windows compatibility
When exFAT was introduced, Microsoft saw a greater need for a filesystem that could bridge the gap between Windows systems and removable storage media that required a file system not limited by FAT32’s maximum 4GB file size.
Since Windows was the dominant OS on most PCs, enhancing Windows compatibility with various storage devices was the more pressing priority that dictated exFAT’s initial development focus.
Limited use cases on Mac at the time
In the mid to late 2000s when exFAT was created, Macs had more limited usage of external storage drives compared to Windows PCs. Features like Time Machine backup didn’t arrive until 2007, so there was less need for very large storage or backup drives required for Macs at the time.
The more pressing need for exFAT readiness was on Windows, which resulted in the priority being support for Windows first before non-Windows operating systems.
Alternatives like FAT32 and HFS+ were available
Since FAT32 and HFS+ were already established file systems that Mac could read and write to, there was less urgency on Apple’s end to adopt exFAT quickly when it required licensing negotiations.
For Macs that needed to interface with large external drives formatted with exFAT, Apple recommended reformatting them with a compatible file system like FAT32 or HFS+ instead of native exFAT support.
How to make exFAT drives compatible with Mac
Despite the later adoption of exFAT capabilities, any modern version of Mac OS from the last 5-10 years now includes full support for reading and writing exFAT drives.
For older versions of Mac OS, Apple created a free exFAT compatibility update to enable exFAT drive functionality.
Therefore, to ensure an exFAT drive can work properly on both Windows and Mac, you should:
- Update your Mac to the latest OS version possible that includes integrated exFAT support
- If running an older OS, install Apple’s exFAT update for compatibility
- Reformat the drive to a cross-platform file system like FAT32
Why exFAT was created
exFAT was introduced by Microsoft to bridge a gap that was emerging between file system requirements and capabilities:
- FAT32 had a maximum 4GB file size limit, inadequate for large media files
- NTFS offered larger file size support but was proprietary to Windows
- A new file system was needed with large file support and cross-platform compatibility
exFAT delivered large file size and storage support combined with much better device compatibility than NTFS. However, Microsoft prioritized Windows support first before expanding exFAT device and OS support further.
Benefits of exFAT
Despite the initial limitations in non-Windows OS support, exFAT does offer some key benefits:
- Supports individual files up to 16EB (exabytes)
- No realistic file size or storage device size limitations
- Faster read/write speeds compared to FAT32
- Lightweight and low overhead for flash drives
- Compatible with Mac OS X 10.6.5 and later
Limitations of exFAT
exFAT does have some limitations to be aware of despite its advantages:
- No built-in file permissions or encryption
- No journaling for greater data integrity
- Higher chance of data loss or corruption if improper disconnection
- Slower at deleting and writing lots of small files due to allocation table
Reasons FAT32 may be a better choice
Despite the very large maximum file size limits of exFAT, in some cases FAT32 can still be a better option:
- Supported natively by every major OS by default
- Journals writes for better data integrity
- Wide range of devices have built-in FAT32 compatibility
- Less licensing issues or proprietary systems involved
Therefore, if you don’t have a specific need to store files over 4GB in size, FAT32 can potentially be more reliable and hassle-free when formatting external drives.
How to format a drive to exFAT in Windows
Here is how to quickly format a drive to exFAT in Windows:
- Connect the external drive to your Windows PC
- Open Windows File Explorer
- Right click on the drive and select “Format…”
- Under “File system” select “exFAT”
- Click “Start” to begin the formatting process
- Confirm by clicking “OK” in the warning prompt
That’s it! Your drive will now be fully formatted and ready for use as exFAT storage.
How to format a drive to exFAT on Mac
Here is how to easily format an external drive to exFAT on Mac:
- Connect the drive to your Mac
- Open Disk Utility (located in Applications > Utilities)
- Select the external drive on the left sidebar
- Click “Erase” at the top
- Under “Format” select “exFAT”
- Click “Erase…” to confirm and begin formatting
Once completed, the drive will now be formatted and accessible as an exFAT volume on your Mac.
In summary, exFAT support was not added to Mac natively until OS X 10.6.5 in 2012 due to:
- Licensing delays between Microsoft and Apple
- Prioritization of Windows compatibility first
- Limited use cases and alternatives available at the time
However, all modern Mac OS versions now have full read/write support for exFAT drives. While FAT32 remains a popular cross-platform choice, exFAT offers distinct benefits for large storage devices thanks to its massive file size limits and fast performance.