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ElectricityCost Guide

Decision tool

Which one costs less to run?

Put up to four appliances side by side at your rate and your hours. The answer is the monthly cost difference — not a wall of specs. The result lives in the link, so you can send it to someone.

A comparison is only useful when the settings match

Hours per day and draw level are the two inputs that change the verdict most. A 1,500 W heater running six hours a day is not comparable to a fan running eight — and a new efficient model can sit at the low end of its range while an old one sits at the high end. Set both cards to the way you actually use them, then compare.

How the monthly figure is calculated

Every card uses the same formula: watts × hours per day ÷ 1,000 × your rate × 30.42. The rate is the EIA residential average for your state unless you enter your own, and 30.42 is the average length of a month — the same constant used on every calculator and state page, so two pages of this site cannot disagree about the same appliance.

The multiple matters more than the dollars. “4.2× as much” stays true whether you run both appliances for one hour or ten; the dollar gap does not. That is why the verdict leads with the ratio and shows the monthly cost underneath.

What the comparison leaves out

  • · Duty cycle. Compressors and heating elements cycle on and off, so a refrigerator rated at 150 W does not draw 150 W for all 24 hours.
  • · Standby draw. Set-top boxes, consoles and chargers consume power while “off”; those loads are priced on their own pages.
  • · Season and efficiency drift. An older unit can sit at the high end of its range, a new one at the low end, and cold weather cuts heat-pump efficiency.
  • · Tariff structure. Tiered and time-of-use plans change what a marginal kWh costs; the state average is a flat baseline, not your tariff.

Comparisons people ask about most

Need a single appliance priced on its own? Every one has a page with its own controls and worked example, starting at all appliances.