How much does it cost to run an air conditioner?
Power times hours times your price per kWh. Nothing more.
With a 1,000 W unit and electricity at $0.17/kWh, it costs $0.17 per hour, $1.36 a day at 8 hours of use and about $41 a month.
Monthly cost by power and use
Swipe to see the whole table
| Power | 4 h/day | 8 h/day | 12 h/day |
|---|---|---|---|
| 700 W | $14.28 | $28.56 | $42.84 |
| 1,000 W | $20.40 | $40.80 | $61.20 |
| 1,300 W | $26.52 | $53.04 | $79.56 |
| 2,000 W | $40.80 | $81.60 | $122.40 |
The formula
That is all there is. All three inputs are yours: the power is on the rating plate, the hours are your choice and the price is on your bill.
What this does not include
- Standing charges, which you pay whether or not you switch anything on.
- Taxes, if the price you use does not already include them.
- Meter rental and other fixed fees.
It is the cost of the energy the unit uses, which is what actually changes when you run it more or less.
Spending less without sweating
- One degree up on the thermostat. It cuts the load and the hours the compressor spends at full power.
- Close blinds before the sun arrives, not after. Blocking radiation beats cooling the result.
- Do not cycle it on and off. Start-ups carry a consumption spike.
- Clean the filters. A dirty filter makes the unit work harder to move the same air.
- Time-of-use tariffs. If you are on one, running off-peak changes the cost noticeably.
A note on tariffs
This site does not download electricity prices or assume any tariff. You enter the price, because it varies by country, supplier, contract and hour of the day, and an automatic figure would create false precision.
Sources and methodology
Conversions use exact constants: 1 BTU/h = 0.29307107 W and 1 frigorie/h = 1 kcal/h = 1.163 W. The component sizing model (load per volume by insulation level, 120 W per person, solar gain by glazed area) is set out in full on the air conditioner size calculator. It is a guideline estimate: a professional heat-load calculation considers considerably more variables.
Frequently asked questions
How much does it cost to run an AC per month?
A 1,000 W unit used 8 hours a day for 30 days at $0.17/kWh costs about $41 a month. The figure moves a lot with the hours of use.
How much does an air conditioner cost per hour?
At 1,000 W and $0.17/kWh, about 17 cents per hour of continuous running.
How do I find my price per kWh?
Divide the energy charge on your last bill by the kWh used. That average reflects your case better than the headline rate.
Is it cheaper to leave the AC on all day?
It depends on the unit and the insulation. An inverter in a well-insulated home can cost less holding temperature than starting from hot several times a day.
How much do I save by raising the thermostat a degree?
It varies, but every degree reduces the cooling load and with it the time the compressor spends at full power.