Free AC energy tool
AC Running Cost Calculator
Estimate daily, monthly, and annual air-conditioner electricity costs with an adjustable compressor load factor and optional model comparison.
Smart result
Your AC estimate will appear here
Rated wattage is adjusted by the editable load factor before energy and cost are calculated.
Why rated wattage is not continuous consumption
An AC compressor cycles or modulates after the room approaches its set temperature. The calculator applies an editable load factor to rated input power instead of assuming full power throughout every operating hour.
Inverter and fixed-speed AC behaviour
Inverter ACs can vary compressor speed, while fixed-speed units generally cycle on and off. Actual consumption for either type depends on room size, insulation, outdoor conditions, thermostat setting, efficiency, maintenance, and usage.
Formula and transparency
Energy (kWh) = watts × quantity × hours × load factor ÷ 1,000. Cost is energy multiplied by your electricity rate. Generic values are estimates; calculation uses the wattage entered by you.
Reference: Generic household ranges and user-entered product data.
Last updated: 19 September 2026.
Frequently asked questions
How many units does a 1.5-ton AC use?+
There is no single figure. It depends on rated input power, compressor load, daily hours, weather, room conditions, thermostat setting, and AC efficiency.
Does inverter AC always save electricity?+
Not always. Inverter control can reduce cycling losses, but savings depend on sizing, usage pattern, operating conditions, and the models being compared.
Does star rating affect running cost?+
A higher-rated model is generally more efficient within its rating cohort, but compare the current energy label and rated or annual consumption for the actual models.
Why does AC consumption change with temperature?+
The temperature difference, humidity, sunlight, insulation, room occupancy, and thermostat setting change how hard and how long the compressor runs.
Is this calculator exact?+
No. It is an estimate from your wattage, runtime, load factor, and electricity rate. A plug-in energy meter or utility sub-meter provides a better measurement.