WattCost

Data through June 2026

What does that appliance actually cost to run?

9,734 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) × 18.3¢/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 2026-08.

  2. 2 · Electricity rate

    State residential rates come from the US EIA's monthly averages — currently 18.3¢/kWh nationally, from 13.1¢ (NV) to 52.7¢ (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