Our tests of dishwasher detergents reveal a big range of differences among formulas and brands. Some can power through baked-on grime and thwart water spots, while some can barely do their fundamental task: clean.
The need for clean reached a new level last year as the pandemic meant many households were eating three meals a day at home and leaning on their dishwashers to take care of the dirty work. Having a dishwasher detergent that gets the job done in one cycle remains a priority.
Detergent pacs and tablets remain the most widely sold type of dishwasher detergent, making up three-quarters of the market. While liquid and powder solvents cost less per load, they can’t match the cleaning power of CR’s top-rated detergent pacs and have fallen out of favor among consumers. In fact, the availability of powder detergents declined so much that CR dropped the category from its tests in 2019.
CR testers apply a baked-on food mixture to eight ceramic dinner plates and load them into a dishwasher, along with bare plates and drinking glasses to fill the machine. After a normal wash cycle completes, we use imaging analysis to determine precisely how clean each dish is and whether any water spots are present. Then we run a set of clear glass dishware and stainless steel plates through a wash cycle with very hard water and use a spectrophotometer to assess whether any haze or discoloration formed on the dishware and metal.
You can choose from three types of dishwasher detergents. Here’s a look at each.
Known as pacs, packets, tabs, and tablets, these single-dose units deliver a conveniently premeasured amount of detergent. This convenience is boosting sales, and CR’s latest tests of detergents found that the best-performing single-dose units clean better than the best gels. That’s because more and more pacs contain one or more additives, such as pretreat solution, degreaser, bleach, and rinse aid, to boost cleaning. Price per load ranges from 9 to 36 cents among the products tested.
This is your least expensive option—the gels we tested cost 5 to 11 cents per load. Although gels can’t match the cleaning power of detergent pacs, two gel detergents we tested do an impressive job cleaning dishes. But the worst of all the detergents we tested is also a gel.
You have to measure out the proper amount for each load, of course, and past tests found that they can get the job done, although they all had a hard time cleaning pots. Sales are dropping as consumers choose pacs and gels, so CR did not include powder formulas in our latest tests.
If your dishwasher has a manual-clean filter, it’s important to clean it regularly. Bits of food end up in the filter, and it’s the filter that prevents food from redepositing debris on clean dishes. Here’s what else to consider.
Skip prerinsing. Most newer dishwashers have a sensor that checks how dirty the water is. The sensor determines the amount of water and time needed to get the dishes clean. But if you prerinse your dishes and the sensor detects little food, the dishwasher gives the dishes a lighter wash, which can leave bits of food on dishes and glasses. Do scrape off dishes and pots, however, before you load them into the dishwasher.
Load right. Your owner’s manual will recommend a loading method that works best for your dishwasher. In general, you want to load large items along the sides and back, so they don’t block the water and detergent. Face the dirtier side of dishes toward the center of the machine, and don’t let dishes or utensils nest together. Place items with baked-on food in the bottom rack, face down toward the sprays. Rest glasses upside down on prongs so that they don’t fill with water. Use the top rack for plastic and delicate items that are dishwasher-safe.
Use a rinse aid. If the dishwasher detergent you use doesn’t contain a rinse aid, consider using a separate one. Rinse aids prevent spotting and improve drying: The rinse aid breaks the bond between the water molecules and dishes, causing water to form sheets and slide off.
Cascade, manufactured by Procter & Gamble, is the leading brand of dishwasher detergent and is sold at many national retailers. Cascade makes a wide variety of detergents, including pacs, gels, and one powder.
Introduced to the American market in 1953, Finish quickly became a leading brand of dishwasher detergent. The brand’s tablets, gels, and powder are now sold in more than 40 countries.
Great Value is Walmart’s private label for a variety of consumer products, including dishwasher detergents.
Kirkland Signature is Costco’s private label. Its dishwasher packs are sold only at Costco warehouses and costco.com.
Member’s Mark is the private label of Sam’s Club, a membership-only retail warehouse club owned and operated by Walmart. Member’s Mark makes dishwasher detergent in pac form only, and it’s sold exclusively at Sam’s Club.
Seventh Generation, a major brand in the green product category, has plant-derived cleaning agents and enzymes. Its lineup includes pacs, gels, and a powder.
Up&Up is Target’s private label for a variety of consumer products, including dishwasher detergents.