Do splines create extra geometry ?

For example to have a pipe with a poly count of 30 and you put a spline on it does it duplicate the amount of poly to 60?


A spline is a non-rendered element that contains no geometry at all so no it does not add to the count.

The spline itself, no, but if you have a mesh being deformed by the spline, every spline segment is another copy of that mesh.