exFAT and FAT32 are two common file systems for storage media like SD cards, USB flash drives, and external hard drives. Both were developed by Microsoft to be used on Windows operating systems.
The exFAT (Extended File Allocation Table) file system was introduced in 2006. It is optimized for flash memory like SD cards, and supports very large file sizes and partitions. exFAT is supported on newer versions of Windows, macOS, and Linux.
FAT32 (File Allocation Table 32) is an older file system that has been around since Windows 95. It supports smaller file sizes and partitions compared to exFAT. However, it has wider compatibility with older operating systems.
When formatting removable media, a key consideration is which file system to use – exFAT or FAT32. The choice depends on factors like partition size limits, individual file size limits, OS compatibility, and more.
What is exFAT?
exFAT (Extended File Allocation Table) is a file system introduced by Microsoft in 2006 for use on flash memory devices and external storage with large capacity and large files (“exFAT File System: Everything You Need To Know”, https://www.minitool.com/lib/extended-file-allocation-table.html). It was designed for use on flash drives and SD cards that are larger than 32GB (“exFAT”, https://en.wikipedia.org/wiki/ExFAT).
exFAT improves upon older file systems like FAT32 by increasing the maximum file size limit to 16EB (exabytes) and the maximum volume size limit to 128PB. This makes exFAT suitable for very large storage devices where files larger than 4GB need to be stored (“Can Microsoft’s exFAT file system bridge the gap between platforms?”, https://arstechnica.com/information-technology/2013/06/review-is-microsofts-new-data-sharing-system-a-cross-platform-savior/).
What is FAT32?
FAT32 (File Allocation Table) is a file system introduced by Microsoft in August 1996 with the release of Windows 95 OSR2.[1] It was designed as an evolution of the FAT16 file system to support larger partition sizes and file sizes over 4GB, while still retaining FAT16’s basic file system logic and concepts.
Some key highlights of the FAT32 file system include:
- Supports partition sizes up to 2 terabytes (TB), versus FAT16’s limit of 2 gigabytes (GB)
- Supports file sizes up to 4GB, versus FAT16’s limit of 2GB
- Uses 32-bit cluster numbers instead of 16-bit, allowing more clusters for larger drives
- Uses smaller cluster sizes for more efficient space allocation on large drives
Overall, FAT32 improved on FAT16’s aging design while maintaining backwards compatibility with existing software. It became the default file system for consumer Windows versions throughout the late 90s and early 2000s. However, it has limitations that newer file systems have aimed to address.
File Size Limits
One of the key differences between exFAT and FAT32 is the maximum file size each file system supports. FAT32 has a maximum file size limit of 4GB per file [1]. This means any file over 4GB in size cannot be saved to a FAT32 formatted disk. In contrast, exFAT supports a virtually unlimited maximum file size of 16 exabytes (EB) per file [2].
The much higher maximum file size limit makes exFAT better suited for large media files like HD video, high resolution photos, and Blu-ray ISO images that can easily exceed 4GB in size. FAT32 would be unable to store these larger files whereas exFAT has no issues supporting them. If you need to store and transfer large files, exFAT is the better choice over FAT32.
Partition Size Limits
FAT32 has a maximum partition size of 8 TB exFAT vs. FAT32 Comparison, while exFAT supports partitions up to 128 PB, or over 15 million TB according to exFAT vs FAT32 – Full Comparison 2024. Because of its ability to handle extremely large partitions, exFAT is better suited for external storage devices with very high capacities. FAT32’s 8 TB limit makes it impractical for today’s large external hard drives and USB flash drives.
Compatibility
FAT32 has wider device compatibility compared to exFAT. FAT32 is supported by Windows 98 and later, while exFAT is only supported starting with Windows Vista. This means that older operating systems like Windows XP can only read and write to FAT32 formatted drives. According to Partition Wizard, FAT32 is compatible with more old OS versions.
In terms of cross-platform compatibility, both FAT32 and exFAT have good support, but FAT32 is slightly better. FAT32 works with all versions of Windows, Mac OS X, Linux, game consoles, cameras, and other devices. ExFAT has good support too, but some older digital cameras may not work with exFAT cards. Overall, FAT32 is the most compatible filesystem for removable media like SD cards.
Performance
When it comes to read and write speeds, tests show that exFAT and FAT32 perform quite similarly in most scenarios. According to benchmark results, exFAT had an average normalized read speed about 5-10% faster than FAT32 across various benchmarks. However, the write speeds were nearly identical between the two file systems.
Some sources note that FAT32 may have a minor edge in performance for very small files, while exFAT is faster for larger files over 4GB in size that are not supported by FAT32. But in most real-world usage with varying file sizes, users are unlikely to notice a significant speed difference between properly formatted drives using exFAT versus FAT32.
Where exFAT does have a more noticeable performance advantage is when used on larger partition sizes. As some sources mention, FAT32 performance tends to degrade on larger drives over 32GB while exFAT maintains faster speeds on larger partitions up to 128TB.
Overall, for general usage, exFAT and FAT32 offer broadly similar read/write performance in most real-world scenarios. The choice between the two is unlikely to make a major impact on speed for typical external storage device usage.
Reliability
When it comes to reliability against corruption, exFAT and FAT32 have some key differences. FAT32 uses cluster chains to store files, which can become fragmented over time leading to data corruption. ExFAT uses a contiguous free space model, storing data in large contiguous blocks which reduces fragmentation and improves reliability.
Furthermore, exFAT includes checksums to help detect corruption during writes. FAT32 does not have any built-in checksum or error correction features. Studies have shown exFAT to have improved robustness against corruption with typical consumer use.1
However, FAT32 may have an edge for reliability during unexpected shutdowns or power loss. The simpler architecture means less chance for data corruption to occur while writes are in progress.
Overall, exFAT’s improvements like checksums provide better robustness against corruption in most real-world usage. But for use cases with more frequent unexpected power loss, FAT32’s simpler design may mean slightly better resilience.
Use Cases
When choosing between exFAT and FAT32, consider the use case for the storage device. FAT32 is a good option for smaller flash drives or SD cards up to 32GB, as it has greater compatibility with older devices. However, FAT32 has a maximum file size limit of 4GB, so it’s not ideal for larger files like movies or disk images.
exFAT is a better choice for larger external hard drives or SD cards above 32GB. It supports much larger file sizes up to 16EB, allowing you to store very large files. exFAT also has no realistic file size or partition size limits for most consumer uses. The main caveat is that exFAT has less compatibility with older devices than FAT32. But it’s supported well on modern versions of Windows, macOS and Linux.
In summary:
- Use FAT32 for smaller flash drives or SD cards up to 32GB, when compatibility with older devices is critical.
- Use exFAT for larger external hard drives or SD cards over 32GB, especially when storing very large files over 4GB.
References:
[1] https://www.howtogeek.com/235596/whats-the-difference-between-fat32-exfat-and-ntfs/
[2] https://www.pcmag.com/how-to/fat32-vs-exfat-vs-ntfs-which-format-is-best-for-your-storage-drive
Conclusion
In most cases, exFAT is the better file system to use over FAT32 for SD cards and external storage drives. The main advantages of exFAT are the ability to store files over 4GB in size, no realistic file size or partition size limits, and broader device compatibility than NTFS. The only downside of exFAT compared to FAT32 is slightly slower performance for very small files. However, for SD cards and external drives that typically store photos, videos, and other large media files, the large file support and lack of limits in exFAT far outweigh any minor performance decreases.
Therefore, for most users today, exFAT is highly recommended over FAT32 for formatting SD cards, external USB drives, and other removable storage. The days of FAT32 being the standard for these devices is mostly in the past, and modern devices and systems now widely support the newer exFAT file system. Unless you specifically need compatibility with older devices that only work with FAT32, such as early digital cameras, portable media players, or game consoles, exFAT is the clear choice for external and removable drives going forward.