Enter the length and width of the picture (or opening) into the calculator to determine the picture frame perimeter (the total distance around it). This calculator can also evaluate the length or width if the perimeter and the other side are known.

Picture Frame Perimeter (Moulding Length) Calculator

Picture Frame Perimeter Formula

The following formula is used to calculate the perimeter (total distance around the rectangle) of a picture frame opening given its length and width:

P = 2L + 2W

Variables:

  • P is the perimeter (total distance around the frame opening)
  • L is the length of the picture (or opening)
  • W is the width of the picture (or opening)

To calculate the perimeter, multiply the length by 2 and the width by 2, then add the results (equivalently, add length and width together and multiply by 2).

What is a Picture Frame Size?

A picture frame size usually refers to the nominal inside size—the artwork/photo dimensions the frame is designed to hold—expressed as width × height (for example, 8″ × 10″). This size is not the outer dimensions of the frame, which are larger because of the moulding. Also, the visible opening at the front can be slightly smaller than the nominal size so the frame overlaps and holds the artwork in place. This calculator does not compute that “width × height” frame size; instead, it computes the perimeter around a rectangular opening from the given length and width.