The toilet is one of the most important items in your home. While the color and cost matter, how much water it uses and how well it flushes matter more. A good one conserves water and generates enough power to clean the bowl in a single flush. (A bad one can be a 20-year pain in the butt.) This article will help you choose a high-performance throne that will fit your bathroom, budget and backside.
#2 -- Measure. Check the rough-in distance, which is the length from the wall to the center of the drain pipe in the floor under the base of the toilet (where the bolts are.) The most common rough-in distance is 12 inches, but it can be 10 or 14 inches. You want to make sure your new toilet has the same rough-in dimensions as your existing toilet or else the toilet will have to be returned or the closet flange will have to be moved and that's a major job.
#3 -- Gallons per flush. Toilets sold in the U.S. use 1.6 gallons of water or less to flush, by law. Toilets installed prior to 1994 use 3.5 GPF, so consider replacing those. Toilet manufacturers have designed the new 1.6 gallon models to out-perform the old 3.5-gallon ones, so don't worry about them not having enough oomph to flush. If you're looking to be even more efficient, 1.28 gallon toilets are also on the market now. Another option is a dual-flush toilet which uses less water for liquids and more for solid waste. Most toilets work by gravity, but there are also "pressure-assisted" toilets which use a pump to give the water more force. (You usually see these in commercial buildings.)
#5 -- Bowl shape and height. Elongated bowls are very popular today, they provide added room and comfort for adults. The shorter round front bowls come in handy in smaller spaces because they can save you 3 or 4 inches in a bathroom. Different heights are also available. Traditional toilet bowls stand approximately 14 1/2" off of the ground. Taller toilets known as comfort height make standing up and sitting down easier and range from 17"-19".