How we test washing machines

All washing machines go through identical tests to let us gauge wash performance, noise levels, and power and water consumption. The exact tests are detailed below.

We use a dedicated test facility which enables us to run side by side tests if necessary, and we run standard tests across all machines. We plumb all washing machines within our test lab, connecting water, drainage and power.

We use the same type of clothes and material load of washing for each machine, although we vary the weight: each machine gets tested at 80% and 50% (half load) of the claimed drum capacity.

Our performance tests

Wash performance: into the regular load we place a test strip, which includes 24-hour dried-on blood, coffee, tumeric, ketchup, blackberry juice and engine oil. We then use a leading non-bio liquid poured directly into the soap drawer and set the washing machine to a standard cotton programme at 40C. We then use the stain strip to measure each washing machine’s stain cleaning performance

Spin performance: by measuring the washing before and after it goes into the machine, we can see how much water is retained after the final spin cycle. We grade machines on the amount of water retained: an additional 29% weight is exceptional; 35% is so-so; higher than this is poor.

Energy and water performance: we measure the water used and energy consumption of a variety of cycles, from standard cotton at 40C through to any Eco modes that are available. This lets us see how the cycles differ and which ones are best to use.

From the default Cotton or Eco Cotton cycle we get our typical running cost per load, priced using average water and electricity unit costs.

To work out yearly running costs, we assume that an annual household wash is 240 loads, split with 200 full loads and 40 half loads. This final calculation lets us compare washing machines from different manufacturers, spotting those with the lowest running costs.

Noise and ease of use tests

We measure the sound in dB of each washing machine. We take measurements during the standard wash phase, where the machine gently spins, and during the spin test, where full rotational speed is reached.

We explain how easy each machine is to load, using our 80% of drum size payload in each case. We examine how easy it is to add detergent, pre-wash fluid and fabric softener. And, we carefully examine each machine examining the build quality.

We examine how easy each machine is to programme and how clearly its controls are laid out. We explain the wash options available and what they do, too.

Scoring and verdict

After all the tests are complete, we score the machine using the criteria outlined in the criteria mentioned here. We first check to see if the machine’s performance matches the manufacturer’s claims, and that all the features work as expected and advertised.