How many watts does a central AC use?
A central AC uses 2,000–5,000 W (about 3,500 W on average). Running 8 hours/day, that is about 28.00 kWh a day and 840.0 kWh a month — roughly $153.80 a month at the U.S. average rate of 18.31 ¢/kWh.
This is the central AC electricity usage reference: watts, amps on a 240 V circuit, the kWh math, and links to what that usage costs in each state.
Watts, amps, and kWh for a central AC
| Measure | Value |
|---|---|
| Rated wattage range | 2,000–5,000 W |
| Average draw used in our math | 3,500 W |
| Amps at 240 V | 8.3–21 A (15 A at the average draw) |
| kWh per hour | 3.50 kWh |
| kWh per day at 8 hours/day | 28.00 kWh |
| kWh per month | 840.0 kWh |
| Cost per month at the U.S. average (18.31 ¢/kWh) | $153.80 |
The math is kWh = watts × hours ÷ 1000 and amps = watts ÷ volts. A central AC is normally wired for 240 V in US homes; a 120 V unit of the same wattage would draw twice the amps. For the dollars in your state, open cost to run a central AC in Texas and switch states from there.
Central AC electricity usage profile
| Metric | Value |
|---|---|
| kWh per hour | 3.50 kWh |
| kWh per day (typical) | 28.00 kWh |
| kWh per month (typical) | 840.0 kWh |
| kWh per year (typical) | 10220.0 kWh |
| Low runtime scenario | 4 hours/day |
| High runtime scenario | 12 hours/day |
Connect usage to cost tools
Related appliance usage pages
Source & Method
Source: U.S. Energy Information Administration (EIA) Retail Sales of Electricity. Last dataset period: July 2026. Usage calculations use fixed appliance wattage and runtime assumptions so results stay comparable across pages.
Frequently asked questions
How many watts does a central AC use?
A central AC uses 2,000–5,000 W (about 3,500 W on average). Our usage and cost math uses 3,500 watts running 8 hours/day.
How many amps does a central AC draw?
On a 240 V circuit, 2,000–5,000 W works out to about 8.3–21 A; at the 3,500 W we use in the math that is 15 A.
How much electricity does a central AC use per month?
About 840.0 kWh a month at 8 hours/day. Lighter use (4 hours/day) comes to roughly 420.0 kWh and heavier use (12 hours/day) roughly 1260.0 kWh.
How much does it cost to run a central AC?
About $153.80 a month at the U.S. average rate of 18.31 ¢/kWh — from roughly $106.85 in Louisiana to $403.20 in Hawaii at the same usage. The state cost-to-run pages price it at every state's rate.