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<Dishwasher detergents
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  5. How we test dishwasher detergents

How we test dishwasher detergents

Find out what's behind our expert lab testing of dishwasher detergents.

Updated July 2026
  • Overview
  • Compare (26)
  • Buying guide
  • How we test

Don't waste your money on a dud detergent. We put them to the test on six stains, including egg yolk and baked-on cheese.

On this page

  • About our test

The overall score is the average of the six scores for removing stains caused by:

  • egg yolk

  • rice starch

  • baked-on cheese

  • red wine

  • coffee

  • minced meat.

About our test

We test in a controlled lab environment using a standard dishwasher designed for domestic consumers, set to a standard “normal” cycle. Each detergent is tested four times on each type of stain. The stained tiles we test with are used by consumer organisations and manufacturers all around the world to simulate everyday food stains. To assess how well the detergents have cleaned, we measure the reflectance of the tiles with a spectrophotometer before and after cleaning.

We also note the recyclability claims on the packaging, the safety information and first aid advice and some environmental claims, such as septic tank and grey water safe and if the product claims to be biodegradable, and what biodegradability standard if stated. These do not contribute to the overall score of the product but are often worth noting.

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