Electricity Cost Calculator

Calculate how much your appliances cost to run. See your monthly electric bill breakdown by appliance and category with real state-by-state electricity rates.

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Select your state, then add appliances from the list above — or click "Load Typical Household" for a quick estimate.

How to Calculate Your Electricity Cost

Understanding Your Electric Bill

Your electric bill is determined by how many kilowatt-hours (kWh) you consume multiplied by your rate per kWh. The formula is simple:

Monthly Cost = (Watts × Hours/Day × 30) ÷ 1,000 × Rate per kWh

For example, running a central air conditioner (3,500W) for 3 hours per day at the national average rate of $0.173/kWh costs about $54.50 per month — making it the single biggest electricity expense in most homes.

Electricity Rates Across the US

Electricity rates vary dramatically by state. As of 2025, the cheapest states are North Dakota ($0.118/kWh), Idaho ($0.118/kWh), and Nebraska ($0.123/kWh). The most expensive are Hawaii ($0.406/kWh), California ($0.325/kWh), and Massachusetts ($0.305/kWh).

The national residential average is about $0.173/kWh, but rates have been rising. Energy costs increased 5.4% nationally in 2025, with some states seeing double-digit increases.

What Uses the Most Electricity?

In most American homes, the top electricity consumers are:

  1. Heating and cooling (40-50%) — Central AC, space heaters, and furnace blowers dominate most bills. A central AC unit running 3 hours/day costs $50-60/month at average rates.
  2. Water heating (14-18%) — Electric water heaters run continuously and account for a large share of usage.
  3. Appliances (15-20%) — Refrigerators, clothes dryers, ovens, and dishwashers add up.
  4. Lighting (5-10%) — Switching from incandescent to LED bulbs can cut lighting costs by 75-85%.
  5. Electronics (5-10%) — TVs, computers, gaming consoles, and standby power draw.

How to Lower Your Electricity Bill

The highest-impact changes you can make:

  • Switch all bulbs to LED: A home with 30 incandescent bulbs switched to LED saves $150-250 per year.
  • Use a smart thermostat: Proper temperature scheduling saves 10-15% on heating/cooling.
  • Eliminate phantom loads: Unplugging chargers and standby devices saves $100-200/year.
  • Run appliances off-peak: If your utility offers time-of-use rates, shifting laundry and dishwasher to evenings can save 20-30%.
  • Upgrade old appliances: A new Energy Star refrigerator uses 40% less electricity than models from 15 years ago.
  • Air seal and insulate: Proper insulation reduces heating/cooling costs by 15-20%.

Seasonal Considerations

Your electric bill likely fluctuates significantly by season. Summer bills can be 2-3x higher than spring/fall due to air conditioning. In cold climates with electric heating, winter bills spike similarly. Use this calculator with seasonal usage hours to estimate your bill throughout the year.

Frequently Asked Questions

How is electricity cost calculated?+
Electricity cost is calculated with the formula: Cost = (Watts × Hours used × Days) ÷ 1,000 × Rate per kWh. For example, a 1,500W space heater running 3 hours per day at $0.16/kWh costs: (1,500 × 3 × 30) ÷ 1,000 × $0.16 = $21.60 per month.
What is a kWh (kilowatt-hour)?+
A kilowatt-hour (kWh) is the standard unit for measuring electricity consumption. It represents using 1,000 watts of power for one hour. For example, a 100-watt light bulb running for 10 hours uses 1 kWh. Your electric bill charges you per kWh consumed.
How much electricity does the average US home use?+
The average US household uses about 899 kWh per month (10,791 kWh per year), according to the EIA. This varies widely by state — Louisiana averages 1,140 kWh/month while Hawaii averages 515 kWh/month. Climate (heating/cooling needs) is the biggest factor.
Why is my electricity rate different from the state average?+
State averages include all utilities and rate plans. Your actual rate depends on your specific utility company, rate plan (tiered, time-of-use, flat), and usage level. Check your electric bill for your exact rate per kWh — it is usually listed as 'Energy Charge' or 'Price per kWh.'
What uses the most electricity in my home?+
The biggest electricity consumers in most homes are: central air conditioning (30-50% of summer bills), water heaters (14-18%), clothes dryers (6%), refrigerators (5%), and lighting (5-10%). Space heaters and pool pumps are also major consumers when in use.
How can I lower my electricity bill?+
The most impactful steps are: switch to LED bulbs (saves $100+/year), use a programmable thermostat (saves 10-15%), run appliances during off-peak hours if on time-of-use rates, unplug phantom loads (chargers, standby devices), air-seal your home, and upgrade old appliances to Energy Star models.
Does this calculator account for standby power?+
The wattage values in our appliance database represent active-use wattage. Most electronics draw small amounts of standby (phantom) power when plugged in but turned off — typically 1-5 watts per device. For a typical home, phantom loads add $100-200 per year to your electric bill.
How accurate are the appliance wattages?+
Our wattage database uses typical values from the US Department of Energy and EIA. Actual wattage varies by model, age, and usage pattern. Refrigerator wattage (150W) represents the average draw over 24 hours, accounting for compressor cycling. Check the label on your appliance or use a kill-a-watt meter for exact measurements.

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Electricity Cost Calculator — free online electricity cost calculator, electric bill calculator, electricity usage calculator, kWh calculator, appliance energy cost, how much does it cost to run, energy cost calculator, power consumption calculator, electric bill estimator, appliance electricity cost calculator, electricity price by state, home energy calculator. No signup required. Works in your browser.