Desktop Computer electricity cost calculator
In this example, a desktop computer at 200W and 70% duty cycle costs $0.025 per scheduled hour. At 8.00 hours per day, that is $6.19 per 30.44 use days, using the August 2026 US average of 18.16¢/kWh. Adjust the calculator for your appliance and electricity bill.
Desktop Computer electricity cost calculator
Use watts and running time, or enter energy from a label, meter or completed load. Your inputs stay on this device.
Enter a number within each field’s limits to calculate your cost.
Your estimated energy cost
409 kWh across 365 use days per year
Power mode includes your selected duty cycle. The monthly figure assumes 30.44 use days; the annual total uses your selected use days. These are estimates at the entered rate.
Energy charges only. Fixed utility fees, purchase, installation and maintenance are excluded. See the calculation method and sources.
Running cost at different usage times
These examples hold 200W, 70% duty cycle and 18.16¢/kWh constant. They illustrate the arithmetic, not recommended schedules. Follow the manufacturer’s operating instructions.
| Hours per use day | kWh per day | Cost per day | 30.44 use days |
|---|---|---|---|
| 0.5 | 0.070 kWh | $0.01 | $0.39 |
| 1 | 0.140 kWh | $0.03 | $0.77 |
| 4 | 0.560 kWh | $0.10 | $3.10 |
| 8 | 1.120 kWh | $0.20 | $6.19 |
How to estimate your desktop computer electricity use
Desktop power changes between idle, office work, gaming and other demanding tasks. The wattage printed on a computer power supply is its output capacity, not a statement that the PC constantly draws that many watts from the wall.
A power-supply capacity, CPU thermal rating or graphics-card rating is not total computer wall consumption. This tool estimates electricity only, not hardware or software cost.
- Use wall-power measurements for the workloads you actually run. A component power estimate or software reading may omit other components and power-supply losses.
- Calculate each operating period separately: average kW while working x working hours, plus average kW while idle x idle hours, plus any sleep or off-mode energy.
- For an illustrative 200W wall draw over six hours, energy use is 1.2 kWh and cost is $0.24 at $0.20/kWh. This is a scenario, not a rating for every desktop.
- Add monitors and other separately powered equipment only if they are excluded from the measurement. A power-strip measurement can already include the whole desk.
Calculation and data sources
Daily kWh = watts ÷ 1,000 × hours × duty cycle ÷ 100. Multiply kWh by your rate in dollars per kWh to get cost. The wattage, hours and duty cycle above are editable example assumptions, not EIA measurements of this appliance.
The US and state average prices come from the EIA for August 2026. A state average is a starting point; your bill is the better source for your tariff.
Electricity running cost by state
Sorted by average electricity price. These reference figures use 8.00 hours per day at 70% duty cycle, for 30.44 days per month and 365 days per year. Seasonal use will cost less than this year-round scenario. Click a state to load its rate.
| State | Rate /kWh | Per month | Per year | Relative |
|---|---|---|---|---|
| Nevada | 12.72¢ | $4.34 | $52.00 | |
| Louisiana | 12.87¢ | $4.39 | $52.61 | |
| Utah | 13.31¢ | $4.54 | $54.41 | |
| North Dakota | 13.31¢ | $4.54 | $54.41 | |
| Idaho | 13.37¢ | $4.56 | $54.66 | |
| Tennessee | 13.42¢ | $4.58 | $54.86 | |
| Nebraska | 13.54¢ | $4.62 | $55.35 | |
| Kentucky | 13.80¢ | $4.70 | $56.41 | |
| Arkansas | 14.37¢ | $4.90 | $58.74 | |
| Wyoming | 14.43¢ | $4.92 | $58.99 | |
| Mississippi | 14.43¢ | $4.92 | $58.99 | |
| Washington | 14.63¢ | $4.99 | $59.81 | |
| Oklahoma | 14.82¢ | $5.05 | $60.58 | |
| North Carolina | 14.95¢ | $5.10 | $61.12 | |
| Florida | 14.99¢ | $5.11 | $61.28 | |
| Arizona | 15.05¢ | $5.13 | $61.52 | |
| South Dakota | 15.15¢ | $5.17 | $61.93 | |
| Kansas | 15.47¢ | $5.27 | $63.24 | |
| Montana | 15.57¢ | $5.31 | $63.65 | |
| South Carolina | 15.76¢ | $5.37 | $64.43 | |
| Georgia | 15.90¢ | $5.42 | $65.00 | |
| Texas | 15.91¢ | $5.42 | $65.04 | |
| Oregon | 15.92¢ | $5.43 | $65.08 | |
| Missouri | 16.02¢ | $5.46 | $65.49 | |
| West Virginia | 16.31¢ | $5.56 | $66.68 | |
| Alabama | 16.33¢ | $5.57 | $66.76 | |
| New Mexico | 16.51¢ | $5.63 | $67.49 | |
| Indiana | 17.02¢ | $5.80 | $69.58 | |
| Iowa | 17.06¢ | $5.82 | $69.74 | |
| Colorado | 17.17¢ | $5.85 | $70.19 | |
| Minnesota | 17.20¢ | $5.86 | $70.31 | |
| Virginia | 17.64¢ | $6.01 | $72.11 | |
| Delaware | 18.70¢ | $6.38 | $76.45 | |
| Illinois | 19.32¢ | $6.59 | $78.98 | |
| Ohio | 19.38¢ | $6.61 | $79.23 | |
| Wisconsin | 19.41¢ | $6.62 | $79.35 | |
| Maryland | 21.40¢ | $7.30 | $87.48 | |
| Pennsylvania | 21.77¢ | $7.42 | $89.00 | |
| Michigan | 22.99¢ | $7.84 | $93.98 | |
| Vermont | 23.84¢ | $8.13 | $97.46 | |
| Connecticut | 24.51¢ | $8.36 | $100 | |
| New Jersey | 24.61¢ | $8.39 | $101 | |
| District of Columbia | 25.98¢ | $8.86 | $106 | |
| New Hampshire | 27.64¢ | $9.42 | $113 | |
| Rhode Island | 28.18¢ | $9.61 | $115 | |
| New York | 28.65¢ | $9.77 | $117 | |
| Alaska | 29.41¢ | $10.03 | $120 | |
| California | 29.75¢ | $10.14 | $122 | |
| Massachusetts | 30.48¢ | $10.39 | $125 | |
| Maine | 32.11¢ | $10.95 | $131 | |
| Hawaii | 47.18¢ | $16.08 | $193 |
Common questions
How much electricity does a desktop computer use?
In this example, 200 watts at a 70% duty cycle uses 0.140 kWh per scheduled hour. At 8.00 hours per day, that is 1.120 kWh per use day. Your model and operating conditions can differ.
How much does it cost to run a desktop computer for an hour?
The default example costs $0.025 per scheduled hour at the US average of 18.16¢/kWh for August 2026. This includes the selected duty cycle. Enter your watts, duty cycle and electricity price for your own estimate.
Does the annual cost assume I use it every day?
The reference tables use 365 days at the stated daily hours; monthly figures use 30.44 days. These are comparison scenarios, not forecasts. For a heater used on 90 days, enter 90 use days per year in the calculator.
Why does electricity running cost vary by state?
For August 2026, the EIA state averages range from 12.72¢/kWh in Nevada to 47.18¢/kWh in Hawaii. Equal electricity use costs more at a higher rate. Your utility tariff can differ from the state average.
Does a 750W PC power supply use 750 watts all the time?
No. Its rating describes available output capacity. Actual wall input depends on the connected components, their workload and power-supply losses. Use measured wall power for a running-cost estimate.
Should I add my monitor to the PC wattage?
Add it if the PC measurement excludes the monitor. If you measured the entire power strip, adding the monitor again would double-count it.
How can I account for gaming and idle time?
Calculate energy for each mode using its representative average input and hours, then add the kWh. One maximum wattage over all hours can overstate use.