How to identify build number of a macOS installer?

Question

Today I read:

Apple today released an updated golden master (GM) version of macOS Sierra to developers… The new GM seed is build 16A323, while the build released last week was 16A320.

After downloading, in the Finder > Get Info of ‘Install macOS Sierra.app’ I see ‘Version: 12.0.49’ but no build number.

How to identifier the build number of a macOS installer?

My goal is to verify what installer I may be using.

Answer 1

The most reliable way of telling the build number is to check the SystemVersion.plist file inside the installer's OS image file (and not the build number of the installer app itself).

1. Mount /Applications/Install macOS Sierra.app/Contents/SharedSupport/InstallESD.dmg
2. Mount /Volumes/OS X Install ESD/BaseSystem.dmg (hidden file)
3. Open /Volumes/OS X Base System/System/Library/CoreServices/SystemVersion.plist and examine the build number under <key>ProductBuildVersion</key>

Answer 2

To determine the macOS Sierra GM build number use:

cat "/Applications/Install macOS Sierra.app/Contents/Info.plist" | grep -A 1 DTSDKBuild

Please apply the leading portion of the path if your Install macOS Sierra.app resides elsewhere.

Answer 3

Hmm... I know when you're booted from the same major version of the OS (10.12, in this case) you can open System Image Utility and select the Install Assistant from the Sources menu and it'll tell you the build number.

But, it will only show the installer (or other volumes) that it can image, which have to match the major version of the booted system. So if you're in 10.11 now and want to see the build number of a 10.12 installer that won't work.

Answer 4

To determine the macOS High Sierra build number use:

1. Mount /Applications/Install\ macOS\ High\ Sierra.app/Contents/SharedSupport/BaseSystem.dmg
2. Open /Volumes/OS X Base System/System/Library/CoreServices/SystemVersion.plist
3. Find the version number under <key>ProductBuildVersion</key>

Answer 5

MOST UPDATED ANSWER for 2020.

Since macOS Mojave, a lot of things have changed. I hope this newer answer remains valid for at least a couple of releases. I'm listing down few different methods, just in case one becomes obsolete.

Below commands assume you have already cd to /Applications/Install macOS XXX.app/Contents

1. cat Info.plist| grep -A 1 DTPlatformVersion should give you the full version like <string>10.15.6</string>

2. cat Info.plist | grep -A 1 CFBundleShortVersionString should give you should give you the minor version (postfix after 10.x) like <string>15.6.00</string>

3. cat version.plist| grep -A 1 CFBundleShortVersionString should give you should give you the minor version (postfix after 10.x) like <string>15.6.00</string>

4. cat SharedSupport/InstallInfo.plist | grep -E '[0-9]{1,3}\.[0-9]{1,2}\.[0-9]{1,2}' should most probably be able to give you the version in format XX.XX.XX

Answer 6

To find the build number once macOS Sierra is installed:

1. Choose Apple Menu > About This Mac
2. Choose System Report... to start System Information app
3. Choose Software from left side
4. From right side find "System Version: macOS 10.12 (build number here)"