The overall Which? test score is made up of the following star ratings, all determined by our rigorous lab tests.
How we test carpets
Our carpet test involves embedding fine dust into wilton carpet with a heavy roller. We then test how much each vacuum cleaner can suck out of the carpet. The best remove more than 80% of the fine dust.
How we test ease of use during vacuuming
Our ease of use tests are conducted by an independent panel of vacuum cleaner experts and assess how easy it is use the vacuum cleaner in various real life situations, how easy it is to conduct regular maintenance on the vacuum cleaner, such as changing bags and filters, and finally how versatile each vacuum cleaner is for conducting a variety of tasks such as cleaning at various heights and cleaning upholstery.
How we test laminate
We assess how much fine dust a vacuum cleaner can remove from a flat hard floor.
How we test floorboards
A crevice is filled with fine dust, and we see how well each vacuum cleaner removes the dust from deep within the crevice.
How we test suction depletion
We test how well a vacuum cleaner cleans when empty, but also when the bag or container is full of dust and debris.
How we test large debris
A good vacuum cleaner doesn't just need to be able to suck up fine dust. We test how well each vacuum cleaner can deal with the type of large dry spill that you might get in your kitchen, by measuring how much dry rice each vacuum cleaner can suck up. The very best suck up practically all of it, while the worst can pick up less than 30%. Our large debris removal test was introduced in our January 2016 test program.
How we test hair and fibre
Hair and fibre removal can be one of the toughest tasks for any vacuum cleaner, but a good one will suck up hairs and fibres in no time. For our hair and fibre tests we comb real cat and dog hair into wilton carpet and then time how long it takes for each vacuum cleaner to suck it all up, the best can do it in less than 30 seconds, the worst take more than three minutes. We also time how long it takes to clean the brush bar after vacuuming. Additionally, our fibre removal from upholstery test involves timing how long it takes to clean fluff and lint from a cushion using the upholstery tool.
How we test allergen retention
We test how much of the nasty fine dust and allergens sucked up by the vacuum cleaner are trapped in its filters and not blown out of the vacuums exhaust.
How we test noise
The higher the star rating, the quieter the vacuum cleaner.
How we test energy consumption
The higher the star rating, the less energy it takes to vacuum your home.