Computer Electricity Cost Calculator: PC & Laptop
Calculate the cost of your actual workload, rather than the rating on the power supply.
Your usage
Example inputsResults update as you type. All costs are in U.S. dollars. See result ↓
For your own rate, add per-kWh supply and delivery charges; leave out fixed fees. Find it on your bill →
Example result — edit inputs to match your use
Estimated electricity cost45 kWh per month at 18.31¢/kWh
(250 W ÷ 1,000) × 6 h × 30 days × 100% × $0.1831 = $8.24At these watts and active time: $0.05 per scheduled hour.
Daily is one day of use. Annual repeats your monthly schedule 12 times (not a 365-day forecast). Rates are held constant. Actual use may vary.
↑ Edit inputsA 750 W power supply does not mean 750 W of use
A power supply’s wattage is its output capacity. Wall draw depends on your components, workload, and power-supply efficiency. Enter a measured average for gaming, office work, or another task. The 250 W and 6-hour starting values are examples. Include your monitor in the measurement if you want the complete setup.
Compare work, gaming, and idle time separately
Run separate estimates for different power levels and add their kWh when the sessions occur on the same day. Do not count the same hours twice. The result excludes sleep and standby power unless it is part of the measured average. Compare two computers under similar workloads, rather than assuming both draw maximum power.
Does sleep mode make a meaningful difference?
The saving depends on the difference between measured idle and sleep power and the number of hours. Compare those two settings using the same hours and rate in the comparison calculator.
Make the estimate yours
Replace the example values with measurements or the product label. Select your state for an official average, then override it with your bill’s variable rate when available.
Read the calculations and assumptionsComputer cost at different electricity rates
This static worked example uses 250 W × 6 hours/day × 30 days × 100% active time. These chosen rates show price sensitivity; they are not utility offers. The interactive result above uses your edited inputs.
| Electricity price | Monthly cost | Annual cost* |
|---|---|---|
| 12¢/kWh | $5.40 | $64.80 |
| 20¢/kWh | $9.00 | $108.00 |
| 30¢/kWh | $13.50 | $162.00 |
*Annual cost repeats this monthly pattern 12 times. Use your actual season length for seasonal equipment. Values are rounded only for display.
Practical energy guides
Watts to kWh: Calculate Energy Use and Electricity Cost
Convert watts, kilowatts, and minutes into kWh with worked examples. Learn why a wattage alone cannot tell you monthly electricity use.
Understand your billHow to Find Your Electricity Rate on Your Bill
Find the right cents-per-kWh rate for an appliance calculator. Separate supply, delivery, fixed fees, and time-of-use charges with a worked bill example.