What version of OS X originally shipped on my mac?

Solution 1:

I use the program Mactracker when I want to know about specific machines throughout Apple's History. With your model number you can identify all there is to know about that mac you have.

It is available form the App Store for both Mac and iOS devices.

Solution 2:

Apple has a knowledgebase article that shows which versions of OS X shipped with which Macs, going back to 2006. It's available via the link below:

https://support.apple.com/HT204319

Some of these articles are no longer showing 10.6 and 10.7 information as progress marches forward, so you may need to use archive.org to research what these articles looked like in the past. One notable article that lost some very good technical information is HT1159 which listed the builds that shipped with hardware across the years.

https://web.archive.org/web/20150223074747/http://support.apple.com:80/en-us/ht1159