A dishwasher that isn't cleaning dishes as well as it used to, or smells off, almost always needs a clean of its own first. Here's the full process.
Food particles, grease, and hard water deposits build up in the filter, spray arms, and door seal over time — and once that buildup is significant enough, it actively reduces how well the dishwasher cleans, creating a frustrating cycle where dishes come out worse despite using the same detergent.
Most modern dishwashers have a removable filter at the bottom, under the lower spray arm. Remove it, rinse it under hot water, and scrub off any trapped food debris with an old toothbrush. This is the single most impactful step and the one most people have never done, sometimes for years.
Check the holes in the spray arms for clogs — a toothpick or thin wire works well to clear them. Clogged spray arm holes are a common, under-diagnosed reason for dishes coming out less clean than expected.
Food debris and grime collect along the rubber door gasket, similar to a front-load washing machine. Wipe this down with a damp cloth, checking the bottom edge where debris tends to settle.
Place a cup of white vinegar on the top rack and run a hot, empty cycle. This helps break down grease and mineral deposits throughout the interior. A dishwasher-specific cleaner works as an alternative or addition.
If you have hard water, a cloudy film on the interior walls and dishes is common. Dishwasher-specific descaling products handle this better than vinegar alone for significant buildup.
Wipe down the control panel and exterior door, including the handle — a frequently touched, infrequently cleaned surface.
Check and rinse the filter monthly, with a full cleaning cycle (vinegar or dishwasher cleaner) roughly once a month as well — more often if you notice odor, cloudy dishes, or reduced cleaning performance.
If dishes still aren't coming out clean after a thorough cleaning, the issue may be water temperature, detergent type, or a mechanical problem rather than buildup — worth ruling out cleaning first since it's the most common and easiest fix, but not assuming it's always the answer.
A dishwasher that isn't performing well usually needs its own cleaning before anything else — the filter specifically is the step most people have never done. If the rest of the kitchen (or home) needs attention too, get a free price estimate for professional cleaning.
Our calculator gives ZIP-code specific prices across all 50 states. Free and instant.
Calculate My Cost →