Finding the OS X version

Finding the version and build number

To find the build number of the version of OS X you have installed, use these steps:

  1. From the Apple menu, choose About This Mac. The version number of OS X you’re using appears directly below the words “OS X.”
  2. Click the version number to see the specific build number of OS X you are using.
OS X Yosemite

OS X Mavericks and earlier

You can also find your version and build number in System Information.

The version and build number you see depends on the version of OS X installed on your computer. When you install an OS X software update or upgrade, you get a new version and build number. The build number of retail versions of OS X and versions available from Software Update are listed below. The build number of OS X releases included with certain Macs might be different from the one that appears below, even if the version number is the same.

OS X Yosemite

OS X Yosemite v10.10.2 Build 14C109
OS X Yosemite v10.10.1 Build 14B25
OS X Yosemite v10.10 Build 14A389

OS X Mavericks

OS X Mavericks v10.9.5 Build 13F34
OS X Mavericks v10.9.4 Build 13E28
OS X Mavericks v10.9.3 Build 13D65
OS X Mavericks v10.9.2 Build 13C64
OS X Mavericks v10.9.1 Build 13B42
OS X Mavericks v10.9 Build 13A603

OS X Mountain Lion and Lion

OS X Mountain Lion v10.8.5 Build 12F37, 12F45 or 12F2029 (see notes)
OS X Mountain Lion v10.8.5 Build 12F37
OS X Mountain Lion v10.8.4 Build 12E55
OS X Mountain Lion v10.8.3 Build 12D78
OS X Mountain Lion v10.8.2 Build 12C54, 12C60, or 12C2034 (see notes)
OS X Mountain Lion v10.8.1 Build 12B19
OS X Mountain Lion Build 12A269
OS X Lion v10.7.5 Build 11G56 or 11G63 (see notes)
OS X Lion v10.7 Build 11A511


  • Build 12F2029 is available for the iMac (21.5-inch, Late 2013) with NVIDIA GeForce GT 750M only.
  • If you have Mountain Lion v10.8.5 (build 12F37), the OS X v10.8.5 Supplemental Update can be installed to get OS X v10.8.5 (build 12F45).
  • If you have Mountain Lion v10.8.2 (build 12C54), the OS X v10.8.2 Supplemental Update 1.0 can be installed to get OS X v10.8.2 (build 12C60).
  • Build 12C2034 is available for certain Macs only; it is installed by the OS X 10.8.2 Update (13″ MacBook Pro with Retina Display, 21.5″ iMac (Late 2012), and Mac mini (Late 2012).
  • If you have OS X Lion v10.7.5 (build 11G56), the Mac OS X v10.7.5 Supplemental Update can be installed to get OS X v10.7.5 (build 11G63).

OS X Snow Leopard and earlier builds

Mac OS X v10.6.8 Build 10K540 or 10K549
Mac OS X v10.5.8 Build 9L30, or 9L34 for Server 10.5.8 v1.1
Mac OS X v10.4.11 Build 8S165
Mac OS X v10.4 Tiger installation disc Build 8A428
Mac OS X v10.3.9 Build 7W98
Mac OS X v10.3.2 installation disc Build 7D28
Mac OS X v10.3 Panther installation disc Build 7B85
Mac OS X v10.2.8 Build 6R65 or 6R73
Mac OS X v10.2.3 installation disc Build 6G37, 6G35 for Server
Mac OS X v10.2 Jaguar installation disc Build 6C115
Mac OS X v10.1.5 Build 5S60 (5S66 with Networking Update 1.0)
Mac OS X v10.1 Puma installation disc Build 5G64 (5L14 or 5L17b with Security Update 10-19-01)
Mac OS X v10.0 Cheetah installation disc Build 4K78

Retail installation disc build numbers

Mac OS X v10.6.3 Install DVD Build 10D575
Mac OS X v10.6 Snow Leopard Install DVD Build 10A432, build 10A433 for Server
Mac OS X v10.5.6 Install DVD Build 9G66
Mac OS X v10.5 Leopard Install DVD Build 9A581