WattCost

Data through April 2026

What does that appliance actually cost to run?

9,441 ENERGY STAR certified models, priced against every state's residential electricity rate. No guesses — the certified test figure, times your rate.

certified kWh/yr (ENERGY STAR) × 18.8¢/kWh (EIA, your state) = $/year

Categories — certified data

Cost to run, by state

Calculators — for devices without certified data

ENERGY STAR doesn't certify annual energy use for everything (space heaters, pool pumps…). For those, transparent watts × hours × rate estimates:

Where the numbers come from

  1. 1 · Energy use

    Every model's annual kWh comes from EPA ENERGY STAR certification data — measured under standardized DOE test procedures, updated 2026-07.

  2. 2 · Electricity rate

    State residential rates come from the US EIA's monthly averages — currently 18.8¢/kWh nationally, from 12.3¢ (ND) to 46.6¢ (HI).

  3. 3 · The math

    Multiply, divide by 100, done. Every figure on this site is reproducible — the full methodology shows the formula and its limits.

Rankings