File size limits and large media files
A file-size limit restricts one file independently of the volume's total free space, which matters for long recordings and high-bitrate media.
A volume can have plenty of free space and still reject a large movie. Free space is the amount available for allocation; a file-size limit is the largest single file the format and implementation can represent.
FAT32 is the familiar example. Its file-length field is 32 bits, giving a maximum of 4,294,967,295 bytes, or 4 GiB minus one byte. A 5-GB file exceeds that boundary even on a nearly empty, much larger volume.
Why the units matter
One decimal GB is 1,000,000,000 bytes. One GiB is 1,073,741,824 bytes. A displayed value near “4 GB” can therefore conceal which side of FAT32's boundary the file actually occupies.
| Candidate file length | Fits the FAT32 field? |
|---|---|
| 4,000,000,000 bytes | Yes |
| 4,294,967,295 bytes | Yes, exactly at the field limit |
| 4,294,967,296 bytes | No |
| 5,000,000,000 bytes | No |
Available space, application behavior and other limits still apply to entries marked “Yes.”
Duration can turn an ordinary bitrate into a large file
For a constant 20-Mbit/s payload, reaching the boundary takes approximately:
4,294,967,295 bytes × 8 ÷ 20,000,000 bits/s
= 1,717.986918 seconds
≈ 28 minutes 38 seconds
Container overhead consumes additional bytes. Variable bitrate changes accumulation over time. The example explains the order of magnitude; it is not a guaranteed recording duration.
Splitting a recording into several files changes the organization and requires suitable application support. Renaming a file or changing its extension does not reduce its byte length.
Other limits remain separate
exFAT and commonly deployed modern file systems can support much larger files. Their actual supported limits depend on format fields, allocation parameters, operating-system implementation and sometimes application APIs. A theoretical field maximum is not a claim that a particular installed system can create a file of that size.
A path-length error concerns the name used to reach a file. A quota concerns an account's or directory's allocation. A full disk concerns available capacity. These failures may all occur during a copy, but they call for different evidence. Check the source file's exact length and destination format before interpreting a failed large transfer.