Ceiling Fixture Size Calculator

A common designer rule for the diameter of a ceiling fixture is to add the length and width of the room in feet and use that number as the diameter in inches. A room that is 12 by 14 feet suggests a fixture about 26 inches across. This calculator uses rules like that for flush mounts, semi flush fixtures, pendants, fans, and chandeliers, and treats them as a starting point that you can adjust to your taste.

A chandelier or a pendant over a table should be narrower than the table, often by about 12 inches in total, so that people do not bump their heads. Hang it about 30 to 36 inches above the table surface. Ceiling fans are sized by blade span, with about 42 inches typical for small rooms and 52 inches for larger ones, and the blades should be at least seven feet above the floor.

Ceiling height matters. In rooms with low ceilings, flush or semi flush fixtures save headroom, and tall rooms can carry larger pendants and chandeliers. Also think about how much light you need, since a decorative fixture may not provide enough general illumination by itself and often needs to be paired with other light sources.