Baseboard Calculator

Walk the perimeter at floor level, where the wall meets the floor, and add up the wall lengths. Then take off the width of each doorway, because baseboard stops at an opening and does not run across it. Closets count if they are getting trimmed.

10% on a plain rectangular room, which covers miter cuts and the ones you cut backwards. Closer to 15% once there are lots of corners, a bay window, or angled walls. Go 15-20% on patterned molding, where every joint has to line up and a bad cut wastes the whole length.

8, 10, 12, and 16 feet are the standard stock lengths. Set the field above to what your supplier actually carries. Longer stock means fewer joints on a long wall, and joints in the middle of a wall are the ones that show.

If baseboard is going in them, yes, so include their perimeter. For a room that is not a simple rectangle, break it into rectangles, work out each perimeter, and add them together before applying waste.