HomelabWatts

Homelab Power Cost Calculator

Homelab Power Cost Calculator: Enter average power draw in watts, hours per day and your electricity price per kWh to see what a device costs to run each month and year. The calculation runs entirely in your browser.

Energy / month
Cost / month
Cost / year
CO₂ / year

Estimate only. Real draw varies with load, PSU efficiency and attached drives.

How it works

Annual energy = watts ÷ 1000 × hours per day × 365. Multiply by your price per kWh for the yearly cost; divide by twelve for the monthly figure. Everything updates as you type and nothing leaves your device. Not sure of a device's draw? Browse the wattage database.

Frequently asked questions

Is the homelab power cost calculator free?

Yes — it runs entirely in your browser, with no sign-up and nothing sent to a server.

How accurate is the cost estimate?

It uses the standard formula watts × hours × kWh price shown on this page. Accuracy depends on the wattage you enter — measure your real draw with a plug-in meter for the best result.

Last updated: 2026-06-13