The file is too large for the volume's format: why a 5 GB video will not copy to your USB stick
Your Mac refuses to copy a big file to a USB stick that has plenty of room. The cause is a 4 GB limit in the drive's format, and the fix takes two minutes.
The drive says 60 GB free. The video is 5 GB. Finder still says: The item can't be copied because it's too large for the volume's format. Nothing is wrong with the drive or the file.
The cause: FAT32 cannot hold a file over 4 GB
Most USB sticks and many SD cards ship formatted as FAT32, called MS-DOS (FAT) on a Mac, because every computer, TV and car stereo can read it. FAT32 has a hard limit: no single file can be 4 GB or larger. Free space does not matter. A long 4K video, a disk image or a backup archive will all hit it.
# See what format a drive uses (replace the name with yours)
diskutil info /Volumes/USBSTICK | grep -i "file system personality"The fix: reformat as exFAT or APFS
| Format | Largest file | Works with |
|---|---|---|
| MS-DOS (FAT32) | Just under 4 GB | Almost everything |
| ExFAT | No practical limit | Mac and Windows, most newer TVs and cameras |
| APFS | No practical limit | Macs only |
| Mac OS Extended | No practical limit | Macs only, and older Macs |
If the drive only ever connects to Macs, choose APFS. If it also goes to a Windows PC, choose ExFAT. Formatting a drive for Mac and Windows covers that choice in more detail.
- Open Disk Utility from Applications, then Utilities.
- Choose View, Show All Devices, then select the drive itself, not only the volume under it.
- Click Erase. Pick ExFAT or APFS, and GUID Partition Map as the scheme.
- Click Erase, wait a few seconds, and copy the file again.
If you cannot reformat the drive
When the drive belongs to someone else, or a device only reads FAT32, split the file instead. A zip archive can be split into parts under 4 GB from Terminal:
zip -s 3900m -r video.zip MyVideo.movThat makes video.zip, video.z01 and so on. All parts must be copied together and joined on the other side. For video, making the file smaller is often simpler: see compressing video on a Mac.
Common questions
Why can't I copy a file to my USB drive when there is enough space?
The drive is probably formatted as FAT32, which cannot store any single file of 4 GB or more. Reformat it as ExFAT or APFS in Disk Utility, after copying off anything you need.
What format should a USB drive be for Mac and Windows?
ExFAT. Both Mac and Windows can read and write it, and it has no 4 GB file size limit.
Does reformatting a USB drive delete everything?
Yes. Erasing in Disk Utility removes everything on the drive, so copy your files somewhere else first.