The overall Which? test score is made up of the following star ratings, all determined by our rigorous lab tests.
How we test grass cutting ability
We test each mower's ability to cope with cutting standard, long grass, rough grass, and wet grass lawns, judging how tidily it cuts the grass and what it's like to use it in different conditions.
How we test handling difficult terrain
Not all gardens are flat and obstacle free, so we test how the mower handles uneven ground, slopes, lawn edges, and how close to wall edges you can cut.
How we test grass collection
We assess how full the grass collector becomes before it needs to be emptied and how often we have to empty it to complete our cutting tests. We also assess how easy it is to remove, carry, empty and replace the grass collector.
How we test mulching ability
We judge how well the mower is able to mulch with the relevant accessory attached. A good mulching mower will chop up the grass clippings finely and redistribute them over the lawn evenly, so they rot down to return nutrients to the turf.
How we test ease of use
We test how easy it is to manouvre the mower, carry and empty the grass collector, clean and store away the mower, adjust the handles and cutting height, and the comfort of the handles, controls and operating position.
How we test quietness
We monitor the noise levels when the mower is in use and give it a rating based on how quietly it runs.
How we test energy efficiency
We find out how much of an impact mowers will have on your bills by measuring how much electricity or fuel they use when mowing our test lawns.