How do BidBrain measure CoS?

We measure Cost of Sales based on the cost and the conversion value from your Google Ads tracking.

We always measure it from Google Ads.  CoS is calculated by dividing Adspend or cost with Conversion value while ROAS is calucalted with Conversion value divided byt Adspend or cost. You can read more on how Google Ads track conversion and and the attribution models available here.