Going to be tough to match a color based on a computer image, since everyone's monitor is different. I'm betting that comes from one of the historic color palettes from either Benjamin Moore or Sherwin Williams. Here are a couple of similar colors, but your best bet is to take the photo to a paint store and compare it to their swatches.

This is Waterbury Green from Benjamin Moore, which is close, but the color above looks to have a bit more blue in it:

Here's BM's Brewster Gray, also similar:

Sherwin Williams retreat 6207 :)

Similar Porch Swing BM

and 25% lighter is Puritan Gray BM