Electricity Cost Calculator
Calculate how much it costs to run any appliance. Get daily, monthly, and annual energy usage and cost estimates.
Check the label on your appliance or its manual for wattage
US average is ~$0.16/kWh. Check your utility bill for your exact rate.
About This Calculator
This electricity cost calculator helps you estimate how much it costs to run any electrical appliance or device. Simply enter the wattage, how many hours per day you use it, and your electricity rate to see your daily, monthly, and annual energy consumption and costs. Use the preset dropdown to quickly fill in common appliance wattages.
Finding your electricity rate: Your electricity rate is listed on your utility bill, usually expressed in cents or dollars per kilowatt-hour (kWh). In the United States, the average residential rate is about $0.16 per kWh, but rates vary significantly by state and utility provider. Some areas charge as low as $0.10/kWh while others exceed $0.30/kWh. If your bill uses tiered pricing, use your highest tier rate for a conservative estimate.
Understanding kilowatt-hours: A kilowatt-hour is a unit of energy equal to using 1,000 watts for one hour. For example, a 100-watt light bulb running for 10 hours uses 1 kWh. Your utility company charges you based on how many kWh you consume each billing period. The formula is simple: multiply the wattage by the hours of use, then divide by 1,000 to get kWh.
Phantom and standby power: Many devices continue to draw power even when turned off or in standby mode. This is called phantom power or vampire power. Common culprits include TVs, game consoles, chargers, and computers. Phantom loads can account for 5 to 10 percent of your total electricity bill. Using power strips with on/off switches or smart plugs can help eliminate standby power draw.
Energy-saving tips: To reduce your electricity costs, consider switching to LED bulbs, which use up to 80 percent less energy than incandescent bulbs. Use a programmable thermostat for heating and cooling. Run dishwashers and washing machines with full loads. Unplug devices when not in use. Look for ENERGY STAR certified appliances when making new purchases, as they meet strict energy efficiency guidelines set by the EPA.
Last updated: April 21, 2026· Reviewed by the CalcNeeds Team
About This Calculator
This electricity cost calculator shows you exactly how much it costs to run any appliance or device. Enter the wattage, how many hours per day you use it, and your electricity rate, and the tool returns daily, monthly, and annual cost estimates along with total energy consumption in kilowatt-hours (kWh). It works for anything that plugs into the wall — from a single light bulb to a central air conditioner.
Understanding your electricity costs is the first step toward reducing them. Most households have no idea which appliances consume the most power. This calculator lets you compare devices side by side so you can make smarter decisions about usage patterns, upgrades, and energy-efficient alternatives.
The national average electricity rate in the United States is roughly $0.16 per kWh, but rates vary widely — from under $0.10 in states like Louisiana and Idaho to over $0.30 in Hawaii and parts of New England. Check your most recent utility bill for your exact rate.
How kWh billing works
Your electric utility charges you by the kilowatt-hour (kWh), which is a unit of energy — not power. One kWh equals 1,000 watts of power used continuously for one hour. A 100-watt light bulb running for 10 hours uses exactly 1 kWh. A 2,000-watt space heater uses 1 kWh in just 30 minutes.
The formula is straightforward: Watts x Hours / 1,000 = kWh. Multiply the result by your rate per kWh to get the cost. If your rate is $0.15/kWh and you run a 1,500-watt heater for 8 hours, the cost is 1,500 x 8 / 1,000 x $0.15 = $1.80.
Your monthly bill also includes fixed charges, delivery fees, and sometimes demand charges, but the kWh usage charge is typically the largest component and the one you have the most control over.
Common appliance wattages
Heating and cooling: Central air conditioner (3,000-5,000W), window AC unit (500-1,500W), space heater (1,500W), ceiling fan (10-75W). HVAC is the largest electricity expense in most homes, accounting for roughly 40-50% of the total bill.
Kitchen appliances: Refrigerator (100-400W running, but cycles on and off), electric oven (2,000-5,000W), microwave (600-1,200W), dishwasher (1,200-2,400W), coffee maker (800-1,400W). Refrigerators run 24/7 but use less total energy than you might expect because the compressor only runs part of the time.
Electronics and lighting: Desktop computer (60-300W), laptop (30-70W), LED bulb (7-15W), incandescent bulb (60-100W), TV (50-200W), gaming console (45-300W). Switching from incandescent to LED bulbs typically cuts lighting costs by 75-80%.
Laundry: Clothes dryer (2,000-5,000W), washing machine (350-500W). The dryer is one of the most power-hungry appliances in any home. Line drying when possible can save $50-100 per year.
Peak versus off-peak electricity rates
Many utilities offer time-of-use (TOU) pricing, where electricity costs more during peak demand hours and less during off-peak periods. Peak hours are typically weekday afternoons and early evenings (roughly 2 PM to 7 PM) when air conditioning loads are highest. Off-peak rates can be 30-50% cheaper than peak rates.
If your utility offers TOU pricing, you can save significantly by shifting heavy usage to off-peak hours. Run your dishwasher, laundry, and pool pump at night or early morning. Charge electric vehicles overnight. Pre-cool your home in the morning before peak rates kick in.
Not all utilities offer TOU plans, and some charge a higher base rate in exchange. Check with your provider to see if switching makes sense for your usage patterns. This calculator uses a flat rate, so if you are on a TOU plan, enter your average blended rate for the best estimate.
How to read your electric meter and bill
Your electric meter measures total kWh consumed. Older analog meters have spinning dials — your usage for a billing period is the difference between the current reading and the previous one. Digital smart meters display the reading directly and transmit data to your utility automatically.
On your bill, look for the usage line (measured in kWh), the rate per kWh, and any tiered pricing. Some utilities charge a lower rate for the first block of kWh (e.g., the first 500 kWh at $0.10) and a higher rate for additional usage (e.g., $0.15 per kWh above 500). If your utility uses tiered pricing, enter the rate for the tier where most of your usage falls.
Tips for reducing your electricity costs
Upgrade to LED lighting. If you still have incandescent or CFL bulbs, switching to LEDs is the single easiest energy upgrade. LEDs use 75% less electricity and last 15-25 times longer. A household that replaces 30 incandescent bulbs with LEDs can save $150-200 per year.
Manage your thermostat. Every degree you raise your AC setpoint in summer (or lower your heat setpoint in winter) saves roughly 3% on heating and cooling costs. A programmable or smart thermostat automates this by adjusting temperatures when you are asleep or away.
Unplug phantom loads. Many devices draw power even when turned off — TVs, game consoles, chargers, and cable boxes are common culprits. These phantom loads can add up to 5-10% of your electricity bill. Use smart power strips to cut power to devices automatically when they are not in use.
Choose efficient appliances. When replacing appliances, look for the Energy Star label. An Energy Star refrigerator uses 10-15% less electricity than a standard model. Energy Star certified washers use about 25% less energy and 33% less water than regular models.
Frequently Asked Questions
How much does it cost to run a space heater all day?
A typical 1,500-watt space heater running 24 hours uses 36 kWh. At the national average rate of $0.16/kWh, that costs $5.76 per day or about $173 per month. Running it only 8 hours per day drops the cost to about $1.92/day or $58/month.
How much electricity does a refrigerator use per month?
A modern Energy Star refrigerator uses about 30-50 kWh per month, costing $4.80-$8.00 at average rates. Older models from the 1990s or earlier can use 100-150 kWh per month. Check the yellow EnergyGuide label on your fridge for its estimated annual consumption.
How do I calculate my electricity cost per hour?
Multiply the device wattage by 1 hour, then divide by 1,000 to get kWh, then multiply by your rate. For a 100-watt device at $0.16/kWh: 100 x 1 / 1,000 x $0.16 = $0.016 per hour, or about 1.6 cents.
What uses the most electricity in a house?
Heating and cooling typically account for 40-50% of a home electricity bill. Water heating is the second largest at 12-18%. After that, the biggest consumers are the clothes dryer, electric oven, and lighting. The exact breakdown depends on your climate, home size, and appliance efficiency.
How many watts does a TV use?
Modern LED TVs use 30-100 watts depending on screen size. A 55-inch LED TV typically draws about 60-80 watts. Older plasma TVs used 150-300 watts. Running a 75-watt TV for 5 hours a day costs roughly $2.19 per month at average electricity rates.
How much does it cost to charge an electric car?
Most electric vehicles use 25-35 kWh per 100 miles. At $0.16/kWh, charging costs about $4.00-$5.60 per 100 miles — roughly one-third to one-quarter the cost of gasoline for a comparable car. A full charge for a 300-mile range EV costs about $12-$17 at home.
What is a kilowatt-hour (kWh)?
A kilowatt-hour is a unit of energy equal to 1,000 watts used for one hour. It is the standard billing unit for electricity. Running a 1,000-watt appliance for 1 hour, a 500-watt appliance for 2 hours, or a 100-watt appliance for 10 hours each consumes exactly 1 kWh.
How much does it cost to run air conditioning per month?
A central AC unit (3,000-5,000 watts) running 8 hours per day costs roughly $115-$192 per month at $0.16/kWh. A window unit (1,000-1,500 watts) running the same hours costs $38-$58 per month. Actual costs vary based on thermostat settings, insulation, and outdoor temperature.
Does turning lights off actually save money?
Yes, but the savings depend on the bulb type. Turning off a 60-watt incandescent bulb for 1 hour saves about 1 cent. Turning off a 10-watt LED saves about 0.16 cents. Over a year, keeping unused lights off can save $20-$50 depending on how many bulbs you have and how long they would otherwise run.
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