Server energy and electricity cost calculator
Estimate kWh and electricity cost using average measured power. The starting values are illustrative assumptions, not measured hardware specifications. Inputs stay in this page; calculating does not call an AI service.
Try the worked four-DGX H100 rack example: a hypothetical 7,000 W average per server versus a constant 10,200 W maximum-rating scenario. Both use four servers, 720 hours, assumed PUE 1.40 and an illustrative rate of 0.12 per kWh. The maximum scenario is not typical measured consumption.
Worked example
With the initial assumptions, A uses 12 kWh of IT energy and 14.4 kWh including facility overhead. At 0.15 per kWh, electricity cost is 2.16 currency units. B uses four times that energy: 300% more. Enable JavaScript to calculate your own inputs.
Formulas and measurement boundaries
IT kWh = average W × server count × hours ÷ 1,000
Facility kWh = IT kWh × PUE
Energy cost = facility kWh × price per kWh
B/A ratio = B facility kWh ÷ A facility kWh
Percentage more = (B/A − 1) × 100If your wattage already includes cooling and power-distribution overhead, select the facility boundary. The calculation then uses PUE = 1 to avoid counting overhead twice. A zero-energy baseline has no defined ratio or percentage increase. The constant-average model does not capture load changes unless your input is a representative average for the period.
PUE relates total facility energy to IT energy; see the LBNL data-center energy report. The tool models electricity energy charges only. Demand charges, time-of-use schedules, taxes, hardware costs and a cloud provider’s bill require additional information.
For a defensible hardware comparison, measure the same useful task, quality and latency requirements. A manufacturer’s maximum rating and another machine’s benchmark average are different quantities. Read the AI versus ordinary server power guide for documented examples and a measurement checklist.