The dishwasher is your go-to cleaning machine, especially after a big family meal, when the countertop is piled high with dirty plates, cookware, serving platters, and the like. Now and then, you need to return the favor by giving your dishwasher a thorough cleaning. This will keep the machine running smoothly and looking its best, while also preventing nasty odors from wafting into the kitchen.

Consumer Reports’ dishwasher tests involve a punishing mix of baked, caked, and dried-on foods. That helps us identify the top-performing dishwashers on the market. It also gives us special insights into what it takes to keep a dishwasher clean and fresh. The following expert tips will help you properly clean a dishwasher.

Step 1: Clean the Exterior

If your dishwasher front is made of plastic, use a sponge and hot, soapy water to wipe it down. For stainless steel dishwashers, glass cleaner is effective at removing built-up grime, as well as smudges and fingerprints. Avoid spraying the cleaner directly onto the dishwasher front, since the moisture could damage its electronic controls. Instead, spray the cleaner onto a paper towel or soft cloth and then apply the cloth to the dishwasher.        

Step 2: Clear the Filter

This step is vital if you have a manual-clean filter, which are common on newer machines. These filters eliminate the grinder on self-cleaning dishwashers that pulverize food scraps and send them down the drain. The result is much quieter operation, but it also means more scraps getting trapped in the filter, leading to funky smells.

That’s especially true if you follow our advice and don’t pre-rinse dishes; most new dishwashers deliver solid results without the extra water-wasting step. In fact, pre-rinsing can actually lead to dirtier dishes by misleading the machine’s sensors into thinking the load is cleaner than it is, resulting in a less thorough wash cycle. 

Okay, back to the filter cleaning. Once a week or so, pull out the bottom rack and remove the filter system, which usually consists of several interlocking parts. There’s often a center cylinder that unscrews, allowing you to lift out the system and take it apart. Clean the parts individually at the sink, using the spray on your faucet or a sponge; our testers also keep a small brush handy to dislodge coffee grounds and other grainy soil that can clog the mesh filter material.

This is also a good time to check the spray arm for trapped food scraps. It usually lifts off its base with a gentle tug. Rinse the arm under the faucet, inspecting for clogged holes, which can be cleared with a toothpick or wooden skewer. Some spray arms have an additional hole on their underside that’s meant to shoot water into the filter, keeping it clean. Check it for clogs before reinstalling the spray arm and filter system. 

Step 3: Sanitize and Deodorize

Over time, discolorations can form throughout a dishwasher’s interior, especially in homes with hard water. Odors will also penetrate the material. White vinegar is a remedy for both issues. Place a clean bowl with a couple cups of vinegar toward the center of the bottom rack. Then run the dishwasher on the normal cycle without detergent. The dispersal of vinegar throughout the cycle should leave your dishwasher sanitized and deodorized.

If the discoloration persists, because of severe mineral deposits from your home’s hard water, you’ll need to switch to a tougher store-bought dishwasher cleaner. We tested three dishwasher detergent additives: Finish Power Up Booster Agent, Glisten Dishwasher Cleaner & Hard Water Spot Remover, and Lemi Shine Original. They all performed well, with Lemi Shine offering the best overall value.