Mac OS X: Mac OS Extended format (HFS Plus) volume and file limits

Learn the limits for files and volumes on disks that use the Mac OS Extended format (HFS Plus) in Mac OS X, including journaled, encrypted, and case-sensitive volumes.

This article has been archived and is no longer updated by Apple.
Volume and file limits in Mac OS X

Maximum number of volumes (all Mac OS X versions)

no limit

Maximum number of files (or files and folders) in a folder (all Mac OS X versions)

up to 2.1 billion (2)

Maximum volume size and file size (Mac OS X v10.0 - 10.1.5)

2 TB (1)

Maximum volume size and file size (Mac OS X v10.2 - 10.2.8)

8 TB (1)

Maximum volume size and file size (Mac OS X v10.3 - 10.5.2)

16 TB (1)

Maximum volume size and file size (Mac OS X v10.5.3 or later)

close to 8 EB (1,3)


  1. The theoretical maximum file size for a Mac OS Extended file system is millions of terabytes. In practice, the maximum file size is equivalent to the maximum volume size, except for a small amount of disk space reserved for file system information.
  2. Specifically, 2^31, or 2,147,483,648. However, the actual number of files that can be stored on a Mac OS Extended (HFS Plus) or journaled HFS+ volume depends on the volume's size and the size of the files. For example, a 160 GB Mac OS Extended volume with the default block size of 4 KB has 40 million available blocks. This volume could store up to 40 million very small files, but not 2 billion. A bigger disk with the same default block size could hold proportionately more files.
  3. 2^63 - 2^31 = 9,223,372,034,707,292,160, which is just under 8 exabytes (EB). One exabyte is roughly equivalent to one million terabytes.
Published Date:Tue Jul 26 21:13:07 GMT 2016