This Is the Best Way to Load a Dishwasher According to Science

By Regina Sienra on June 10, 2024

open dishwasher with dishes on the racks

What's the best way to load a dishwasher? There seems to be as many possibilities as stars in the sky, but as with all things, the best course of action may be checking in with science. Kate Yoshida of MinuteFood enlisted two experts—Dr. Rainer Stamminger, professor in the Institute of Agricultural Engineering at the University of Bonn, and appliance repair technician Renae DuHaime—to get some insight into this query and to settle the age-old question once and for all.

Yoshida, who knows the importance of optimizing and having clean tools at hand, has always been inclined to the science side of food. To start her research, she set up a GoPro through an active dishwasher cycle to see how her own dishwasher worked. By determining how temperature, water rotation, and detergent work together to remove stubborn food stains, she had a framework to make the most out of this appliance.

“You want to put your dishes close together to maximize the amount of stuff you can fit in there, but not too close, because you don’t want to block those little streams of water from actually getting stuff clean,” Yoshida says. “If you don’t have a full load, haphazard approach isn’t that big a deal—just avoid overlapping dishes that are particularly dirty.” And you don't have to pre-rinse them before placing them in; all they need is a good scrape to remove any leftovers.

The same principle applies to utensils. “Should they go in eating-surface down, or eating-surface up? This according to the experts, direction doesn’t actually matter; your utensils should get clean whether they’re facing up or down—and this was basically confirmed by the vaguely-scientific tests I ran. What DOES matter is keeping utensils from snuggling tight together—in other words, don’t let your spoons ‘spoon’—because again, water won’t be able to get between them.” She adds that you can avoid them by mixing different kinds of utensils in each bin with some face down and others face up.

Ultimately, her conclusion is that, if your dishes aren't getting properly cleaned, there may be something wrong with your dishwasher, so it may be best to have it checked. After all, these machines were built to save us all time—up to 230 hours a year, according to the expert. Next time, instead of arguing and wondering about the best way to do it, let it work and enjoy the time it saves you.

To stay up to date with her kitchen discoveries, you can follow Yoshida on Instagram.