What is the latest OS version I can install on a 2015 MacBook Air?

Monterey.

(208452)

I tried Montery and it said I was 6GB short. i have a MacBook Air 7,2. 13" 2015 model, memory 8GB.

Click here and follow the instructions. If you find that the installed RAM(not free disk space) isn't enough to effectively use it, you'll need to downgrade or get a computer with more.

(208552)