Shortening curtains

[mrspez07]

Both boys rooms have had floor length curtains, but when closed it blocks the heating vent unless someone remembers to tuck it in under the blinds on the window sill.
I know floor length curtains are still mostly the trend, but They both want their curtains shortened, and it’s not like it’s a visible part of the house anyway. I can sew them to adjust. The windows are pretty wide, how short would you go? How far below the sill or above the floor is a good rule of thumb?

[redheadk]

I like length B. Doing it a few inches shorter than floor length looks like an accident, IMO. A few inches below the window looks purposeful. I don’t like exact window length, it looks too short

[Deleted]

I agree with redheadk. We have electric baseboards under all of our windows, so floor length curtains aren't an option. In the few rooms that we have regular curtains, we do length B. For the rest we either have just shades or tie-up curtains.