Fat32 file or folder limits

jtsdadinaz · External Since: Apr 05, 2006 Posts: 2

I have not seen the answer to this anywhere yet.

1. What is the actual number oif files you can have in a fat32 folder? I
have one that has 22,657 and can not add any.

2. Can this limit be changed?

Tim Slattery · External Since: Jun 14, 2004 Posts: 256

jtsdadinaz wrote:

>I have not seen the answer to this anywhere yet.
>
>1. What is the actual number of files you can have in a fat32 folder? I
>have one that has 22,657 and can not add any.

A FAT32 directory can have 65,536 directory entries. Each file and
subdirectory takes from two to thirteen entries, depending on the
length of its name, so those entries can disappear long before you
think you've used them all up. Your total of 22,657 files could very
easily use 65,000 entries.

>2. Can this limit be changed?

No.

--
Tim Slattery
MS MVP(DTS)
Slattery_T.RemoveThis@bls.gov

jtsdadinaz · External Since: Apr 05, 2006 Posts: 2

Remind me where I can read up on directory entries per say. My filenames
aren't that long to take more than a couple of entries each. Or is there some
kind of utility that will tel lme how many entries a file uses?

"Tim Slattery" wrote:

> jtsdadinaz wrote:
>
> >I have not seen the answer to this anywhere yet.
> >
> >1. What is the actual number of files you can have in a fat32 folder? I
> >have one that has 22,657 and can not add any.
>
> A FAT32 directory can have 65,536 directory entries. Each file and
> subdirectory takes from two to thirteen entries, depending on the
> length of its name, so those entries can disappear long before you
> think you've used them all up. Your total of 22,657 files could very
> easily use 65,000 entries.
>
> >2. Can this limit be changed?
>
> No.
>
> --
> Tim Slattery
> MS MVP(DTS)
> Slattery_T.RemoveThis@bls.gov
>

Tim Slattery · External Since: Jun 14, 2004 Posts: 256

jtsdadinaz wrote:

>Remind me where I can read up on directory entries per say. My filenames
>aren't that long to take more than a couple of entries each. Or is there some
>kind of utility that will tel lme how many entries a file uses?

The FAT32 spec is available here:
http://www.microsoft.com/whdc/system/platform/firmware/fatgen.mspx

It gives details on everything, including the directory structure and
the way Long File Names (LFNs) are stored in directories.

Basically, there's one directory entry that always holds the short
(8.3) version of the file name. If the actual name doesn't fit that
mold, then there will be one to twelve more entries, each of which
holds 13 bytes of the full name. So a file named
"veryverylongname.txt" would take three entries. The first would have
the short name, something like "veryve~1.txt", the second would have
"veryverylongn", and the third would have "ame.txt".

--
Tim Slattery
MS MVP(DTS)
Slattery_T.RemoveThis@bls.gov