To develop our in-depth toilet ratings, Consumer Reports’ engineers put the fixtures through a battery of tests involving waste removal, bowl cleaning, and drain-line clogs. We also measure how loud a toilet’s flushes are using a decibel meter. Based on performance in these tests, we give each toilet an Overall Score.
To test solid-waste removal, we dump marble-sized plastic beads, weighted sponges, and water-filled condoms into the bowl and measure how well each flush handles the simulated waste.
We use a combination of methods to assess how well a toilet cleans the entire bowl. First, we use water-based red paint to create a solid rectangular shape above the waterline in the front bottom of a clean bowl. We take a picture of the red rectangle, and then the toilet is flushed two times. After the second flush, we take a second picture to record how much of the paint has been removed.
A second way we test how well a toilet cleans waste: We let the bowl fill up, then draw a line using a water-soluble pen around the bowl about an inch under the rim. Next, we flush. We then measure how much of the pen marking is left. The better a toilet cleans, the less marking and paint are left. We repeat the pen test three times and calculate the average to arrive at a score.
To gauge soil and odor potential, we measure the length and width of the bowl, as well as the depth of water inside. The deeper and wider the bowl, the better solid waste odors will be trapped by the water.
We also look at how well a toilet moves waste from bowl to sewer and whether there’s enough force to make sure the waste doesn’t get stuck, especially if waste travels a long way to the sewer.
