What is the max number of files that can be kept in a single folder, on Win7/Mac OS X/Ubuntu Filesystems?

Question

I'm wondering about what is the maximum number of files that can be present in a single folder, in the file systems used by all the prevalent OSes mentioned. I need this information in order to decide the lowest common denominator, so that the folder I'm building can be opened and accessed in any OS.

Answer 1

In Windows (assuming NTFS): 4,294,967,295 files

In Linux (assuming ext4): also 4 billion files (but it can be less with some custom inode tables)

In Mac OS X (assuming HFS): 2.1 billion

But I have put around 65000 files into a single directory and I have to say just loading the file list can kill an average PC.

Answer 2

This depends on the filesystem. The lowest common denominator is likely FAT32 which only allows 65,534 files in a directory.

These are the numbers I could find:

• FAT16 (old format, can be ignored): 512
• FAT32 (still used a lot, especially on external media): 65,534
• NTFS: 4,294,967,295
• ext2/ext3 (Linux): Depends on configuration at format time, up to 4,294,967,295
• HFS+ (Mac): "up to 2.1 billion"

Answer 3

Most modern OSes have no upper limit, or a very high upper limit. However, performance usually begins to degrade when you have something on the order of 10,000 files; it's a good idea to break your directory into multiple subdirectories before this point.