Computer Electricity Cost Calculator
Estimate the running electricity cost of a computer, console or other device from its wattage, hours used and your tariff.
Check your electricity bill for your actual usage rate
Your results
Calculation breakdown
- Daily energy
- (watts × hours ÷ 1000) kWh
- Daily cost
- daily kWh × rate (c/kWh ÷ 100)
Worked example
A 250 W gaming PC used 5 hours a day at 30c/kWh costs about 250 × 5 ÷ 1000 × 0.30 = $0.375/day, or roughly $137/year.
Assumptions
- Electricity rate must be entered from your own bill, as tariffs vary by state, network and retailer.
- Assumes a constant average power draw while in use; actual draw varies with workload.
- Excludes any standby/idle power outside the stated hours of use.
How this calculator works
Calculate the daily, weekly and annual electricity cost of running a PC, gaming console or monitor from its power draw in watts, hours of use, and your electricity rate in cents per kWh from your bill.
Convert computer power into electricity cost
Divide power in watts by 1,000 to convert it to kilowatts, multiply by hours used to get kilowatt-hours, then multiply by your electricity usage rate. A 200 W computer used for five hours consumes about 1 kWh before allowing for other equipment.
Use measured or realistic average power rather than the maximum power-supply rating. Monitors, speakers, network equipment and time spent idle or asleep can be included separately for a better estimate.
- Energy (kWh) = watts ÷ 1,000 × hours
- Cost = energy used × electricity rate
- Use the rate that applies at the time of use
What the estimate does not include
This appliance-level estimate normally excludes the fixed daily supply charge because that charge applies to the whole property. Time-of-use, controlled-load and demand tariffs may require separate calculations using the correct billing periods.
Compare active, idle and sleep scenarios to identify savings without assuming the computer draws its rated maximum continuously.
Official sources and assumptions
Check the underlying Australian Government guidance used to review this calculator's rates and assumptions.
Frequently asked questions
Where do I find my device's wattage?
Check the power supply rating on the device or box, or measure actual draw with a plug-in power meter for a more accurate figure.
Where do I find my electricity rate?
Your usage rate in cents per kWh is shown on your electricity bill or your retailer's plan details; it varies by state, network and retailer.
Does this include standby power?
No, enter an average wattage that reflects your typical usage pattern if you want standby time included.
Editorial review and responsibility
Reviewed by the CalcAussie editorial team on 21 September 2026. Review scope: Method, Australian terminology, material assumptions, source links and user-facing limitations.
Calculator results remain estimates based on the figures entered. Check material decisions against current official information and report a suspected error so it can be reproduced and corrected.
Actual prices, usage, efficiency and savings vary by provider, equipment, location and behaviour.