How to know how many pixels Ad Banner is taking up?

I’ve still got a few things to look into (including whether or not having ad banners outside of my menu is a good idea) but how can I get the dimensions of the ad banner? I presume (from the little information I’ve gained from “Submit your ad banner” pages) that these banners scale to different sizes based on the DPI of the device or something. I can make it so that my users can simply set the “safe area” based on the ad banner but having that be the first decision they have to make before playing the game seems like it casts the ads in a very negative light. In previous games I just presumed that the top 50 pixels of my screen weren’t visible and simply made sure that there weren’t threats from that far out. In this game I can’t really do that. I’m just using the default Admob integration.