This overall score is made up of cooling efficiency (40%), heating efficiency (40%) and airflow (20%).

Cooling and heating efficiency scores are based on the model's AEER (Annual Energy Efficiency Ratio) and ACOP (Annual Coefficient of Performance) – a measure of efficiency that factors in standby power consumption when the unit's not in use. Our scores are more precise than star ratings.

Cooling and heating efficiency scores are based on the model's AEER (Annual Energy Efficiency Ratio) and ACOP (Annual Coefficient of Performance) – a measure of efficiency that factors in standby power consumption when the unit's not in use. Our scores are more precise than star ratings.

Based on the range of airflow on the lowest to highest fan speed settings. Ideally, air conditioners should have a gentle airflow on low settings and a powerful airflow on high. The wider the range of airflows, the better the score.

We recommend air conditioners that score at least 80% overall.

Brand reliability is based on our 2018 member survey and shows the percentage of respondents owning that brand of air conditioner who reported no problems with it in the previous 12 months. "Not available" means we didn't get enough responses to score that particular brand.

Owner satisfaction is based on our 2018 member survey and shows how satisfied respondents who own that brand of air conditioner are with their purchase.

Tested models are currently available. Discontinued models are from previous reviews – note that scoring may have been revised since these models were reviewed.

The recommended or typical retail price at time of publication. You can often get a better price by shopping around.

Based on how much each model costs to deliver a set amount of cooling and heating per year at maximum capacity, with the remainder of the year in standby mode (based on electricity costs of 30 cents/kWh). It's only indicative; your actual running costs may vary. See our How we test article for more.

To help you narrow your search, we class air conditioners as small (up to 4kW cooling capacity), medium (4 to 6kW) and large (over 6kW). Scores are only comparable between models in the same size category, as it's not realistic to compare the efficiency of models with very different capacities.

Noise levels are supplied by the manufacturer. Where available, we show the noise on the quietest indoor fan setting. Noise levels are broadly comparative, but note that different manufacturers may measure these values slightly differently.

Noise levels are supplied by the manufacturer. They're broadly comparative but note that different manufacturers may measure these values slightly differently.

The rated cooling output of the air conditioner in kilowatts. The higher the number, the greater its cooling capacity and (in theory) the bigger the space it can effectively cool.

The rated heating output of the air conditioner in kilowatts. The higher the number, the greater its heating capacity and (in theory) the bigger the space it can effectively heat.

Star ratings are based on regulated standard testing. The more stars, the better; more stars means better efficiency, lower running costs and lower greenhouse gas emissions.

Star ratings are based on regulated standard testing. The more stars, the better; more stars means better efficiency, lower running costs and lower greenhouse gas emissions.

Refrigerant gases are usually R410A or R32. Both are hydrofluorocarbons but R32 has a lower global warming potential and should also give improved efficiency.

A 'powerful' or 'jet' setting that gives a quick performance boost.

A low fan speed designed to be particularly quiet. Some models have a quiet mode for the outdoor unit too; handy for running at night.

This allows the air conditioner to act just as a fan, without cooling or heating; useful if you just want a breeze in the room.

Sleep mode adjusts the air conditioner's output temperature and fan speed (usually in steps) so the temperature becomes more comfortable for sleeping and the air conditioner runs at lower power and more quietly.

"Yes" indicates that the model's sleep mode adjusts the air conditioner's output temperature in steps, so the change is gradual.

This feature detects whether anyone's in the room; if no one's there, the air conditioner switches to an economy mode to reduce power consumption. Some models also direct the air movement towards the sensed person, so as to not cool or heat unused areas.

Allows control of the air conditioner via your home wireless network and an app on your smartphone, so you can power the unit on or off when away from home, set temperatures and monitor energy use. It's not available for all models, but is built-in for some and an optional extra for others.

Demand Response Enabling Device (DRED), also known as PeakSmart. An air conditioner with this feature can be controlled remotely by participating energy companies
to run in a power-saving mode in periods of peak electricity demand. It's not available for all models, but is built-in for some and an optional extra for others.