PC Power Cost Calculator — Estimate Your PC's Electricity Cost
What does a gaming PC actually cost to run?
Electricity is the running cost people most often guess at and most often get wrong — usually by assuming the number on the power supply is what the machine draws. A 1000 W unit does not consume 1000 W; it is a capacity rating, and your system draws what its components actually need at that moment.
This calculator turns a wattage figure and your local electricity price into a cost per hour, day, month and year, so you can see the real number rather than estimating it.
How the cost is worked out
Electricity is billed per kilowatt-hour: one kilowatt drawn for one hour. Multiply your average draw in kilowatts by the hours you use it and by your tariff, and that is the cost. The arithmetic is simple — the difficulty is using a realistic wattage.
Your machine spends most of its life well below peak. Browsing or watching video might draw a small fraction of what a demanding game does. Using a peak gaming figure for all-day usage will substantially overstate the cost, so separate your gaming hours from your idle hours for a number you can trust.
How to use it
- 1Estimate your system draw under load — the PSU Calculator gives a realistic figure for your components.
- 2Enter your electricity price per kWh, which appears on your bill.
- 3Set how many hours a day you genuinely use the machine at that load.
- 4Run it twice, once for gaming hours and once for idle hours, then add the results.
Getting an accurate figure
Use measured draw where you can
An inexpensive wall meter removes all the guesswork and captures power-supply losses too. Failing that, a calculated system figure is far better than the PSU label.
Use your real tariff, including standing charges where relevant
Rates vary enormously by country and by time of day. If you are on a time-of-use tariff, gaming in a peak window costs meaningfully more than the same hours off-peak.
Remember efficiency affects the wall figure
The power your components use is not the power drawn from the wall — the supply loses some as heat. A more efficient unit draws less at the socket for the same system load, though the difference is usually modest in cash terms.
Common mistakes
Using the PSU wattage as the draw
This is the most common error and can overstate running cost several times over. The rating is the maximum the unit can deliver, not what your system consumes.
Applying peak gaming draw to twenty-four hours
Idle draw is a fraction of load draw. Treating every hour as a gaming hour produces a number that bears no relation to your bill.
Buying a high-efficiency unit purely to save money
Better efficiency is worth having for heat, noise and build quality reasons. Recovering the price premium purely through electricity savings usually takes a very long time at typical usage.
Costs are estimates based on the wattage and tariff you enter. Real consumption varies with workload, and electricity prices change — treat the result as a well-informed approximation, not a bill.
Frequently asked questions
How much does it cost to run a gaming PC per month?
It depends almost entirely on system draw, hours played and your tariff. Enter your own figures above — a modest system played a few hours a day and a high-end system running long sessions can differ several times over.
Does a bigger power supply use more electricity?
No. The rating is a capacity limit, not a consumption figure. A system draws what its components need; an oversized unit simply runs at a lower percentage of its capacity.
Is it cheaper to leave a PC on or shut it down?
Shutting down or sleeping uses less. Idle draw is small compared with load, but across a month of continuous uptime it is not nothing — sleep is a reasonable middle ground.
Related tools
- PSU Calculator — get a realistic system wattage
- Thermal Estimator — power drawn becomes heat
- PC Builder — see power draw as you pick parts
Not sure what your system actually draws? Size it from your real components first.
Open the PSU Calculator