The short answer: machine washable kitchen runner rugs are the right idea for the messiest floor in the house, but the label is doing a lot of work. A 2 by 6 runner fits almost any washer. Anything larger depends on your drum, and manufacturers quote minimum capacities that assume a top loader with an agitator, so if yours has no agitator you need to subtract 0.4 cubic feet from whatever number the brand gives you. The other measurement nobody mentions is pile height: at 0.3 inches a runner catches under a dishwasher door, and at 0.2 inches it clears. Get both numbers right and a washable runner is genuinely the best thing you can put in a kitchen. Get them wrong and you have bought a rug you cannot wash and a door that will not open.
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