1. The problem statement, all variables and given/known data Let's say I have a coordinate system that has (0,0,0) at the CM of an object, and I know the object's inertia tensor for that coordinate, T. (T is a 3x3 inertia tensor where (1,1) is moment of inertia about x-axis, (2,2) is moment of inertia about y-axis, and (3,3) is moment of inertia about z-axis). I then rotate the object about its CM by a degrees about x-axis, b degrees about y-axis, and c degrees about the z-axis. I am using the convention where a positive angle rotates the object clockwise if the positive portion of the axis about which rotation is happening is approaching you from your viewing spot. Is there a simple matrix transform I can do to T to find the new inertia tensor, T'? This is for a coding project. As of now, I am recomputing T' for each orientation. I would like to speed things up if possible. I am searching online with little success. If one of you gentlemen or ladies knows the relation off the top of your head, it would save me much time! EDIT: I found something about finding the inertia tensor for a new, rotated coordinate. Is it the case that rotating an object a b and c would be the tensor found about the coordinates rotated -a -b and -c?