How many files can a windows folder contain?

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

Posted 2009-07-31T08:18:30.260

Reputation: 2 390

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 – 2009-07-31T10:01:58.810

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 – 2009-07-31T10:02:49.493

UPDATE: Correct data for NTFS: http://technet.microsoft.com/en-us/library/cc781134%28WS.10%29.aspx

– Richard – 2009-07-31T10:05:31.860

UPDATE: Correct data for FAT: file/partition size: http://support.microsoft.com/kb/314463 and folder entries: http://support.microsoft.com/kb/120138

– Richard – 2009-07-31T10:08:55.050

Any info on if/how performance degrades once one has more than a few thousand files? – Thilo – 2009-09-02T02:26:04.273

@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 – 2009-09-02T14:15:56.573

@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 – 2012-11-28T09:50:21.843

How many files can a windows folder contain?

Answers