from what I vaguely recall from the ~first movie (And whatever that pseudo black hole thing was) he's above Thor base/2 stone thanos etc. and is at least on the level of full power Odin
These, Silver Surfer is absolute bullshit in that movie to the point he makes most characters in the MCU that are stated to be very powerful look like ants.
Just touching him can literally fuck with your powers hardcore, whether they are biologically locked or not, has such control over his molecules to not only pass through inanimate objects but people too as well as Susan's shields and his own board. And he was causing massive EMP bursts just moving around and other natural disasters and that wasn't just blowing holes in the Planet straight to the core easily too.