Free tool
Electricity cost calculator
Enter an appliance's wattage, how long it runs and your utility rate to see what it really costs per day, month and year. Every figure below is calculated in your browser from the numbers you enter — nothing is estimated for you.
- Energy per day
- 9.60 kWh
- Cost per day
- $1.63
- Cost per month
- $48.96
- Energy per month
- 288.0 kWh
- Cost per year
- $595.68
- Share of a $180 bill
- 27%
How the calculation works
Utilities bill residential customers for real energy in kilowatt-hours. One kilowatt-hour is 1,000 watts drawn for one hour. So the formula is simply:
(watts ÷ 1000) × hours per day × days × rate per kWh = cost
The US residential average rate sits near $0.17/kWh, but rates range from roughly $0.11 in parts of the South to over $0.40 in Hawaii and California peak tiers. Check the "price to compare" or "supply rate" line on your own bill for the accurate number.
Where the biggest savings usually are
| Load | Typical share of a US home bill | Fastest lever |
|---|---|---|
| Heating & cooling | ~45% | Thermostat setbacks, filter changes, HVAC service |
| Water heating | ~14% | Lower tank temp to 120°F, shorter showers |
| Appliances & electronics | ~20% | Retire second fridge, kill phantom loads |
| Lighting | ~5% | LED retrofit |
| Everything else | ~16% | Time-of-use scheduling |
For a deeper walkthrough see how to lower your electric bill and what power factor correction actually does.
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Pick the bundle that matches your home size, then complete your order securely on this page — no redirects, no account required.
Sizing rule of thumb: one device per 800–1,200 sq ft, so most homes over 1,500 sq ft use the 3-device bundle.
Checkout — 3 Devices
$105.84
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