Electricity Cost Calculator

Find out exactly how much any appliance or device costs to run — per hour, day, month and year.

Appliance preset (optional — auto-fills wattage)

Wattage

Hours per day

h/day

Days per month

days

kWh rate

$/kWh

Monthly Cost

$43.20

270.00 kWh per month

Per Hour

$0.240

Per Day

$1.44

Per Year

$518.40

Energy usage

Per Day

9.00 kWh

Per Month

270.00 kWh

Per Year

3,240.00 kWh

How to Use This Calculator

This calculator shows exactly how much electricity any appliance costs to run — no guessing, no reading meter graphs. Enter four numbers and get instant results across every time period:

Wattage (W): Find this on the appliance's label, Energy Guide sticker, or product manual. If you see a range (e.g., “600–1,500W” for an adjustable space heater), use the wattage at your normal setting.
Hours per day: How many hours does the appliance actually run? A refrigerator doesn't run 24 hours continuously — it cycles on and off, averaging about 8 hours of compressor running time per day. An AC running “all afternoon” might be 4–6 hours at full power.
Days per month: Use 30 for a full month. For seasonal appliances (summer AC, holiday lighting), use the actual number of days you run it.
kWh rate: Your utility's charge per kilowatt-hour, found on your electricity bill. The US average is $0.16/kWh, which is the default. Rates range from $0.11 in Louisiana to $0.39 in Hawaii.

Use the appliance presets dropdown to auto-fill common wattages for 30+ devices — refrigerators, AC units, washing machines, EV chargers, LED bulbs, and more. Then use Add to appliance comparison to build a household energy audit: add your major appliances one by one and see the running total monthly cost at the bottom of the comparison table.

The calculator updates results instantly as you type. All processing happens in your browser — nothing is sent to a server, and there are no ads or sign-ups.

What Is a Kilowatt-Hour (kWh)?

A kilowatt-hour (kWh) is the unit of electrical energy that appears on every electricity bill, yet most people have never had it properly explained. Here is the core distinction: watts describe how fast energy is consumed (power), while kWh describe how much total energy was consumed over time (energy).

One kilowatt-hour is the energy consumed by a 1,000-watt appliance running for exactly one hour:

kWh = Watts ÷ 1,000 × Hours

To make this concrete, here is how a few common appliances compare on kWh usage:

A 9-watt LED bulb running 1 hour uses 0.009 kWh — about $0.001 worth of electricity.
A 60-watt incandescent bulb running 1 hour uses 0.06 kWh — 6.7× more than the LED for the same amount of light.
A 1,500-watt space heater running 1 hour uses 1.5 kWh — the same energy as running 167 LED bulbs for an hour.
A 5,000-watt clothes dryer running 1 hour uses 5 kWh — enough energy to power a laptop for 100 hours.

The reason this distinction matters: your electricity bill charges you for kWh consumed, not for watts. A 100-watt TV left on for 10 hours uses 1 kWh. A 10-watt LED bulb left on for 100 hours also uses 1 kWh. Same energy cost — but the LED gets you 10× more run time per dollar spent. Understanding kWh lets you compare appliances on a level playing field and identify where your money is actually going.

Watts measure a rate (like miles per hour), while kWh measure an amount (like total miles driven). Every kilowatt-hour on your bill represents 1,000 watt-seconds of electrical energy — the same unit the entire global power grid runs on.

US Electricity Rates by State

The US residential average electricity rate is approximately $0.16 per kWh as of 2024, according to the US Energy Information Administration (EIA). However, this national average obscures enormous regional variation — the difference between the cheapest and most expensive states is nearly 4×, which means the same appliance can cost nearly four times as much to run depending on where you live.

Why rates vary: Electricity prices depend on the fuel mix used for power generation (natural gas, coal, nuclear, hydro, wind, solar), transmission infrastructure costs, local regulations, and population density. States with abundant hydroelectric power (Washington, Oregon) or cheap natural gas (Oklahoma, Louisiana) tend to have lower rates. Island states and densely populated northeastern states with aging infrastructure pay the most.

State	Rate ($/kWh)
Hawaii	$0.39
Connecticut	$0.31
Massachusetts	$0.29
Rhode Island	$0.28
California	$0.27
New Hampshire	$0.25
New York	$0.22
Florida	$0.17
US Average	$0.16
Texas	$0.14
Tennessee	$0.13
Oklahoma	$0.12
North Dakota	$0.12
Louisiana	$0.11

How to find your exact rate:Open your electricity bill and look for a line labeled “energy charge,” “consumption charge,” or “price per kWh.” If your bill only shows total kWh used and total amount charged, divide the total charge by total kWh for your effective rate. Note that this effective rate includes fixed service fees spread across your usage, so it may be slightly higher than the stated per-kWh energy rate.

Time-of-use (TOU) rates: Many utilities now offer time-of-use pricing, where electricity is cheaper during off-peak hours (typically nights and weekends, often 9 PM – 7 AM) and more expensive during peak demand (afternoon and early evening). If your utility offers TOU rates, shifting energy-intensive appliances like dishwashers, washing machines, and EV chargers to off-peak hours can reduce your bill by 10–20%.

What Uses the Most Electricity in Your Home?

The average US household consumes about 10,500 kWh per year — roughly 875 kWh per month. Understanding where that energy goes is the starting point for any meaningful reduction in your electricity bill:

1. Heating and Cooling — 40–50% of total electricity

Central air conditioners draw 2,000–5,000 watts; electric furnaces 10,000–20,000 watts (though they run fewer hours in moderate climates). Heat pumps are the most efficient option, delivering 2–4 kWh of heating per 1 kWh of electricity consumed — compared to 1 kWh of heat per 1 kWh for resistance heating.

2. Water Heating — 14–18%

Electric water heaters draw 3,000–4,500 watts. A family of four with a standard 50-gallon electric heater typically pays $400–$600 per year just for hot water. Tankless heaters are more efficient because they heat water on demand rather than keeping a tank warm all day.

3. Washer and Dryer — 5–7%

Electric clothes dryers are among the most power-hungry household appliances at 4,000–6,000 watts. One dryer cycle (45 min at 5,000W) costs $0.60–$0.90. The washing machine itself is far more efficient at 500–1,000 watts; the energy savings from washing in cold water mainly come from not heating the water.

4. Lighting — 5–9%

A home with 30 incandescent 60W bulbs on for 8 hours/day spends about $86/month on lighting at $0.16/kWh. The same 30 fixtures using 9W LEDs spends $12.96/month — a savings of $73/month or nearly $880 per year, with bulbs that last 15× longer.

5. Refrigerator — 3–4%

Modern refrigerators use 100–200 rated watts but cycle on and off, averaging 1–2 kWh/day. At $0.16/kWh, that is $5–$10/month. Pre-2000 refrigerators can use 3–4× more energy — an old fridge left running in the garage can cost $30+/month on its own.

6. Electronics and Standby Power — 2–4%

TVs (50–200W), game consoles (100–150W), and desktop computers (150–300W) add up quickly. Standby power from devices that are off but still plugged in — cable boxes, phone chargers, game consoles in sleep mode — accounts for 5–10% of total home electricity use, costing the average household about $165/year for electricity that powers nothing useful.

How to Calculate Electricity Cost Manually

The formula this calculator uses is straightforward. Knowing it helps you verify results and understand exactly what you are paying for:

kWh per day = Watts ÷ 1,000 × Hours per day

Cost per day = kWh per day × kWh rate

Cost per month = Cost per day × Days per month

Cost per year = Cost per month × 12

Worked example — space heater: 1,500W running 6 hours/day at $0.16/kWh:

kWh per day: 1,500 ÷ 1,000 × 6 = 9 kWh
Cost per day: 9 × $0.16 = $1.44
Cost per month: $1.44 × 30 = $43.20
Cost per year: $43.20 × 12 = $518.40

Appliance	Watts	h/day	Days	Monthly Cost
Space Heater	1,500	6	30	$43.20
Central AC	3,500	8	30	$134.40
Clothes Dryer	5,000	1	30	$24.00
55" TV	100	4	30	$1.92
Refrigerator	150	8*	30	$5.76
LED Bulb (9W)	9	8	30	$0.35
EV Charger L2	7,200	2	30	$69.12

* Refrigerators cycle on and off — use ~8h/day effective running time, not 24h.

7 Ways to Lower Your Electricity Bill

The average US household spends $1,400–$1,700 per year on electricity. Most of those costs are reducible without sacrificing comfort. Here are the highest-impact strategies, ranked by typical savings:

Adjust your thermostat — biggest single-item impact

The Department of Energy estimates that setting your thermostat back 7–10°F for 8 hours a day (while sleeping or away) saves up to 10% on annual heating and cooling costs. At $1,500/year average HVAC cost, that is $150/year from one habit change. A smart thermostat ($100–$200) learns your schedule automatically and typically pays for itself within the first year through savings alone.

Replace incandescent bulbs with LEDs

LED bulbs use 75–80% less energy than incandescent bulbs and last 15–25× longer. Replacing 20 incandescent 60W bulbs with 9W LEDs saves approximately 852 kWh per year (at 8h/day average) — or $136/year at $0.16/kWh — plus the cost of 20+ bulb replacements you will never need to buy. The payback period for LED replacement is typically under 6 months.

Eliminate vampire loads (standby power)

Electronics and appliances consume power even when turned off — this "standby power" or "vampire load" costs the average US household $165/year. The worst offenders are cable boxes (17W standby), game consoles (1–15W), desktop computers and monitors (5–30W), and phone chargers that stay plugged in. Smart power strips cut power to all devices in a group when the main device (TV, computer) is turned off — no behavior change required.

Use time-of-use rates strategically

If your utility offers time-of-use (TOU) pricing, off-peak hours (often 9 PM – 7 AM on weekdays, plus weekends) can be 30–50% cheaper than peak rates. Run your dishwasher overnight on a delay timer, do laundry on Saturday morning, and schedule your EV charger to start after 9 PM. A household with heavy daytime energy use could save $20–$60 per month by shifting load to off-peak hours.

Upgrade aging appliances to Energy Star models

When a major appliance reaches end of life, the replacement choice has a significant long-term impact. Energy Star refrigerators use 9% less energy than minimum federal standards; washers use 20% less energy and 30% less water; dishwashers use 12% less energy. For a refrigerator running 15 years, the efficiency difference between a standard and Energy Star model can exceed $200 in electricity savings.

Seal air leaks around your home

The EPA estimates that sealing air leaks can save 15% on heating and cooling costs — the most cost-effective single improvement for many homes. Common leak points: gaps around window and door frames, electrical outlets on exterior walls, plumbing penetrations in cabinets, and the attic floor. A $20 tube of caulk and $30 of weatherstripping can pay for themselves dozens of times over their lifetime.

Wash clothes in cold water

Approximately 90% of washing machine energy goes to heating water. Switching to cold water for all loads saves $60–$80 per year with no reduction in cleaning effectiveness for most fabrics — modern detergents are formulated to work in cold water. Cold washing also reduces color fading and extends fabric life, reducing clothing replacement costs over time.

Frequently Asked Questions

What is a kilowatt-hour (kWh) and how is it measured?▼

A kilowatt-hour (kWh) is the standard unit of electrical energy used by utility companies to measure electricity consumption. One kWh equals the energy consumed by a 1,000-watt appliance running for one hour. For example, a 100-watt light bulb running for 10 hours uses 1 kWh (100W × 10h ÷ 1,000 = 1 kWh). Your electricity bill charges you a rate per kWh — typically between $0.10 and $0.40 depending on your state and utility provider.

How do I calculate the electricity cost of an appliance?▼

To calculate electricity cost: (1) Find the appliance wattage on the label or manual. (2) Multiply watts × hours per day ÷ 1,000 to get kWh per day. (3) Multiply by your kWh rate to get daily cost. (4) Multiply by 30 for monthly cost. Example: A 1,500-watt space heater running 6 hours/day at $0.16/kWh costs 1,500 × 6 ÷ 1,000 × $0.16 = $1.44 per day, or $43.20 per month.

What is the average electricity rate per kWh in the US?▼

The US residential average electricity rate is approximately $0.16 per kWh as of 2024 (EIA data). Rates vary significantly by state — the most expensive are Hawaii ($0.39/kWh), Connecticut ($0.31/kWh), and Massachusetts ($0.29/kWh). The cheapest are Louisiana ($0.11/kWh), North Dakota ($0.12/kWh), and Oklahoma ($0.12/kWh). To find your exact rate, check your electricity bill for the "energy charge" or "kWh rate" line item.

What appliances use the most electricity in a home?▼

The biggest electricity consumers in a typical US home are: (1) HVAC systems — 40–50% of total use. (2) Water heater — 14–18%. (3) Washer and dryer — 5–7%. (4) Lighting — 5–9%. (5) Refrigerator — 3–4%. (6) Dishwasher — 2–3%. (7) Electronics — 2–4%. Central air conditioners run 2,000–5,000 watts, electric water heaters 3,000–4,500 watts, and clothes dryers 4,000–6,000 watts. These three alone often account for over 60% of your electricity bill.

How much does it cost to run a refrigerator for a month?▼

A modern refrigerator uses 100–200 rated watts but cycles on and off, averaging about 1–2 kWh per day of actual consumption. At $0.16/kWh, that is $4.80–$9.60 per month. Older refrigerators (pre-2000) can use 2–3× more energy. Energy Star certified models can cost as little as $3–$5 per month. When entering a refrigerator into this calculator, use approximately 8 hours per day to account for the cycling — not 24 hours of continuous running.

How much does it cost to charge an electric vehicle at home?▼

EV charging cost depends on battery size and your kWh rate. Most EVs have 50–100 kWh batteries. A full charge at $0.16/kWh costs $8–$16. A Level 2 home charger draws about 7,200 watts and adds roughly 25 miles of range per hour of charging. For a driver covering 1,000 miles/month in an EV averaging 4 miles/kWh, monthly charging costs 1,000 ÷ 4 × $0.16 = $40 — versus roughly $120–$180 in gasoline.

How can I lower my monthly electricity bill?▼

The highest-impact strategies to lower your electricity bill: (1) Set your thermostat 7–10°F lower when sleeping or away — saves up to 10% annually. (2) Replace incandescent bulbs with LEDs — uses 75% less energy. (3) Unplug standby devices ("vampire loads") — can account for 5–10% of your bill. (4) Run dishwashers and laundry during off-peak hours if your utility offers time-of-use rates. (5) Seal air leaks around windows and doors — saves up to 15% on HVAC costs.

How much electricity does an air conditioner use per month?▼

Window AC units use 500–1,500 watts; portable units 1,000–1,500 watts; central air conditioners 2,000–5,000 watts (1 ton ≈ 1,200 watts). A 3,500-watt central AC running 8 hours/day at $0.16/kWh costs $134 per month. AC systems typically account for 40–50% of summer electricity bills in warm climates. SEER rating determines efficiency — a higher SEER means fewer watts for the same cooling output.

How do I find my kWh rate on my electricity bill?▼

Look on your electricity bill for a line labeled "energy charge," "consumption charge," or "price per kWh." It will show a dollar amount per kWh (e.g., $0.14/kWh). If your bill only shows total kWh and total charge, divide total charge by total kWh to get your effective rate. Many utilities have tiered rates — a lower rate for the first block of kWh and higher rates above. Your bill may also include fixed service fees separate from the per-kWh rate.