A desktop computer uses 120 to 270 watts. At the U.S. average electricity price of 18.31¢ per kWh in July 2026, that costs 2.2¢ to 4.9¢ for every hour it runs. A desktop computer draws about 120 watts while in use, or about 270 watts including a monitor.
Calculate what your desktop computer costs
Cost to run a desktop computer
| Use | kWh | Cost |
|---|---|---|
| One hour | 0.20 | 3.7¢ |
| 1 hour a day for a month | 6.1 | $1.11 |
| 4 hours a day for a month | 24.3 | $4.45 |
| 8 hours a day for a month | 48.6 | $8.91 |
| 4 hours a day for a year | 292 | $53 |
Cost to run a desktop computer in every state
| # | |||
|---|---|---|---|
| 1 | Louisiana | 12.72¢ | $9.29 |
| 2 | Nevada | 12.77¢ | $9.32 |
| 3 | Utah | 13.12¢ | $9.58 |
| 4 | North Dakota | 13.41¢ | $9.79 |
| 5 | Tennessee | 13.71¢ | $10 |
| 6 | Idaho | 13.73¢ | $10 |
| 7 | Nebraska | 13.78¢ | $10 |
| 8 | Kentucky | 13.81¢ | $10 |
| 9 | Arkansas | 14.33¢ | $10 |
| 10 | Oklahoma | 14.35¢ | $10 |
| 11 | Wyoming | 14.36¢ | $10 |
| 12 | Mississippi | 14.54¢ | $11 |
| 13 | Washington | 14.71¢ | $11 |
| 14 | Montana | 14.99¢ | $11 |
| 15 | Florida | 15.03¢ | $11 |
| 16 | North Carolina | 15.16¢ | $11 |
| 17 | Kansas | 15.27¢ | $11 |
| 18 | South Dakota | 15.37¢ | $11 |
| 19 | Arizona | 15.38¢ | $11 |
| 20 | South Carolina | 15.47¢ | $11 |
| 21 | West Virginia | 15.78¢ | $12 |
| 22 | Texas | 15.88¢ | $12 |
| 23 | Oregon | 15.97¢ | $12 |
| 24 | Iowa | 15.99¢ | $12 |
| 25 | Missouri | 16.09¢ | $12 |
| 26 | New Mexico | 16.09¢ | $12 |
| 27 | Georgia | 16.27¢ | $12 |
| 28 | Alabama | 16.40¢ | $12 |
| 29 | Indiana | 16.73¢ | $12 |
| 30 | Colorado | 17.00¢ | $12 |
| 31 | Minnesota | 17.45¢ | $13 |
| 32 | Virginia | 17.55¢ | $13 |
| 33 | Delaware | 18.48¢ | $13 |
| 34 | Wisconsin | 19.06¢ | $14 |
| 35 | Illinois | 19.22¢ | $14 |
| 36 | Ohio | 19.45¢ | $14 |
| 37 | Maryland | 21.41¢ | $16 |
| 38 | Pennsylvania | 21.72¢ | $16 |
| 39 | Michigan | 23.05¢ | $17 |
| 40 | Vermont | 23.75¢ | $17 |
| 41 | Connecticut | 24.16¢ | $18 |
| 42 | New Jersey | 25.19¢ | $18 |
| 43 | District of Columbia | 25.21¢ | $18 |
| 44 | New Hampshire | 26.60¢ | $19 |
| 45 | Rhode Island | 28.29¢ | $21 |
| 46 | Alaska | 28.83¢ | $21 |
| 47 | New York | 29.90¢ | $22 |
| 48 | Massachusetts | 30.49¢ | $22 |
| 49 | Maine | 32.41¢ | $24 |
| 50 | California | 33.61¢ | $25 |
| 51 | Hawaii | 48.00¢ | $35 |
Desktop Computer energy use FAQ
How many watts does a desktop computer use?
A desktop computer typically uses 120 to 270 watts. Check the label on yours for its exact rating.
How much does it cost to run a desktop computer?
At the U.S. average of 18.31¢ per kWh (July 2026), it costs 2.2¢ to 4.9¢ an hour. Used one hour a day, that is $1.11 a month at 200 watts.
Where is it cheapest to run a desktop computer?
With electricity at 12.72¢ per kWh, Louisiana is the cheapest state: $9 a year for 200 W for one hour a day. The same use costs $35 in Hawaii.
Sources: U.S. Department of Energy typical appliance wattages (via Virginia Cooperative Extension); electricity prices: EIA retail sales data (July 2026). Last updated 2026-10-20.