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How many files can a windows folder contain?

This question is asked here but then the question text pollutes the question with issues of "rules of thumb"

So to be clear, this question is: How many files can a windows folder contain?

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Ron Tuffin
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1 Answers1

32

FAT

  • 512 Files Per Folder

FAT32

  • 65,534 Files Per Folder
  • 512 Files for the root directory

NTFS

  • 4,294,967,295 Files Per Folder

(from here)

EDIT: I removed some of the additional information because it was a resulting in down votes and not really necessary to answer the question. Thanks @Richard for the constructive feedback below.

Ron Tuffin
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  • Really not sure about those numbers. FAT (all types) has always had a fairly small limit for root folders (with long file names using multiple limits), but non-root folders could keep growing (linear search means opening a file is going to get much slower with large numbers of files). – Richard Jul 31 '09 at 10:01
  • NTFS does have a file size limit. The NTFS format limits it to 2^64 bytes, but actual driver implementation limit is significantly less (2^48 bytes IIRC). – Richard Jul 31 '09 at 10:02
  • UPDATE: Correct data for NTFS: http://technet.microsoft.com/en-us/library/cc781134%28WS.10%29.aspx – Richard Jul 31 '09 at 10:05
  • UPDATE: Correct data for FAT: file/partition size: http://support.microsoft.com/kb/314463 and folder entries: http://support.microsoft.com/kb/120138 – Richard Jul 31 '09 at 10:08
  • Any info on if/how performance degrades once one has more than a few thousand files? – Thilo Sep 02 '09 at 02:26
  • @Thilo I don't have any concrete numbers on performance. But i am sure it would depend largely on what precisely it is you are trying to do. Getting a file listing will take much proportionatly longer than say opening a specific file, but I am sure that both would take a hit as the file numbers increase. I unfortunately can't (not without a whole bunch of homework) say how big that hit would be. – Ron Tuffin Sep 02 '09 at 14:15
  • @Thilo - I have about 1,000,000 files (plus all the files in the Windows folder that aren't being backed up) on my computer. I don't see a significant or noticeable drive performance change. As Ron suggested, a full directory listing, or searching for a file if I don't have a known path to start from (in other words, searching from the drive root) can take a while, but normal file access is typically as fast as I'd imagine it could be. Depends on what's going on. If backup (to cloud) software is running, and I'm recording a movie (Media Center), it can occasionally get bogged down momentarily. – Kevin Fegan Nov 28 '12 at 09:50