Getting the size right is the single most important decision when buying a chandelier. Too small and it looks lost. Too big and it overwhelms everything else in the room. Here's a practical guide.
The quick formula. Add your room's length and width in feet. Convert that number to inches — that's roughly the right chandelier diameter. So a 12×14 foot room works with a chandelier around 26 inches wide. Simple, and it works surprisingly well as a starting point.
Over a dining table. The chandelier should be about half to two-thirds the width of the table. For a 40-inch round table, that means 20-26 inches. Hang it 30-36 inches above the table surface. For rectangular tables, consider a linear chandelier and match its length to about two-thirds of the table.
Living rooms. Here the chandelier is more of a statement piece than task lighting. You can go a bit bigger than the formula suggests. Just make sure the bottom of the fixture clears at least 7 feet from the floor.
Entryways and stairwells. These spaces can handle taller, more dramatic fixtures since you're usually viewing them from a distance. In a two-story foyer, a chandelier that hangs into the upper portion creates real impact. For stairwells, measure the vertical space carefully — the fixture needs to be visible from both levels without being a hazard.
Ceiling height changes everything. Standard 8-foot ceilings basically require flush or semi-flush mounts. At 9-10 feet, you have room for a small chandelier or pendant. 12 feet and above is where the really interesting options open up.
When in doubt, go bigger. A slightly oversized chandelier makes a confident statement. A slightly undersized one just looks like a mistake. This is one of those cases where "too much" is better than "too little."