How Much Does It Cost to Run a Desktop Computer? (2026)

Desktop power draw varies more than almost any other appliance. An office mini PC idles at 20 watts, while a gaming rig with a high-end graphics card can pull 500 watts or more under load.

A typical desktop computer (150 W) costs $0.028 per hour, or about $6.60 per month at 8 hours a day in the US. Average running cost

Hours used per day
WattagePer hourPer dayPer monthPer year
Low 60 W$0.011$0.088$2.64$32.13
Typical 150 W$0.028$0.22$6.60$80.33
High 500 W$0.092$0.73$22.01$267.76

Formula: watts ÷ 1000 × hours × price per kWh. Typical use is 8 h/day ≈ 438 kWh per year.

One hour of a desktop computer (0.15 kWh) is the same electricity as

Electricity per year at typical use, on a log scale: #69 of 95 appliances, from least to most.

Around the world per year at typical use, local prices

How to lower the cost of running a desktop computer

In standby it draws about 2 W, which adds roughly 18 kWh ($3.21) per year if it is never unplugged.

Is an efficient desktop computer worth it?

Desktop PC with monitor for office work, about 150 W: about 438 kWh a year. Laptop for the same work, about 45 W: about 131 kWh. The difference is worth $56.30 a year in the US.

Usage assumed: 8 hours a day. Typical prices: $900.00 for the efficient model, $900.00 more than a basic one. Work it out with your own prices

Frequently asked questions

How many watts does a gaming PC use?

Between 300 and 600 watts while gaming, depending on the graphics card. Idle draw is typically 50 to 100 watts.

Does leaving the PC on overnight cost a lot?

At 60 watts idle for 12 hours it uses 0.72 kWh, roughly the cost of a few minutes of a space heater.

Does a bigger power supply use more electricity?

No. The PSU only delivers what the components request. A larger unit just has more headroom.

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Cost by region

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Related appliances

Use the generic electricity cost calculator · Which uses more? Take the quiz