We recommend robot lawnmowers with a CHOICE Expert Rating of 80% or more.

The overall score is made up of performance (60%), convenience (20%), noise (10%), instructions (5%) and construction (5%).

Performance is broken down into standard lawn (50%), damp grass (10%), long grass (10%), uneven lawn (10%), sloping lawn (10%) and battery efficiency (10%).

We test on what we define as a standard lawn (200sqm) of 40–50mm long grass which is tested over a four-week period. 

Our testers use the mowers after heavy dew or a light shower so that the grass is uniformly damp.

Our test lawn is grown to 100mm to determine how well the mowers handle long grass.

How well the robot lawnmower copes with an uneven lawn terrain.

How well the mower copes with a sloping lawn.

How well the battery performs, including charging time, average use time and whether the mower automatically returns to its charging station.

Convenience is broken down into installing and using (70%), and the app (30%). Where there is no app, only installing is taken into account.

Installing and using the robot mower includes the following elements: mounting base station, setting perimeter cable, using manual programming, using auto programming, using the remote control, setting cutting height, ease of lifting and carrying robot, cleaning/hosing, and ease of removing and refitting the blade.

Where there is an available app, we assess programming the mower, use as a remote control, surveillance of the mower and safety block or similar features.

Noise is broken down into operation noise measured (50%) and subjective evaluation at 10m from mower (50%).

This score is broken down into whether the mower comes with safety and operating instructions, general information, technical data, instructions for use, setup and programming, maintenance and servicing instructions.

This score is based on how solid the construction feels.

Does the robot stop when the user gets close to it? Is it possible to touch the mower when it's in use? Is it possible to pick up the mower when it's in use? If so, will the blades stop immediately? Do the blades stop automatically? If not, after how many seconds?

Measured sound level in decibels.

Recommended or typical retail price at the time of publication.

This is the recommended maximum lawn size in square metres, as claimed by the manufacturer.

The steepest incline that the mower will be able to handle before it won't be able to climb up to cut the grass.

Rated cutting width, in centimetres, according to the manufacturer.

Battery capacity measured in Amp-hours.

Charging time we found after using the mower on our standard test lawn.

Claimed warranty from manufacturer websites

Does the mower return automatically to recharge?

Whether an alarm sounds if the unit is picked up.

This lets you choose which weather you want the robot mower to work in.

Whether you can program a security code to operate the mower.