Electricity Cost Calculator
Calculate how much it costs to run any appliance or device. Enter the wattage, daily usage hours, and your electricity rate to see the cost per day, month, and year.
How to Use the Electricity Cost Calculator
Estimating the running cost of any appliance takes just a few steps:
- Enter the wattage — Find the wattage on the appliance label, in the owner's manual, or use one of the quick presets above. Wattage is measured in watts (W).
- Enter the hours of use per day — Estimate how many hours per day the appliance runs. For devices that cycle on and off (like a refrigerator), use the average active hours.
- Enter your electricity rate — Check your utility bill for the price per kilowatt-hour. The default is $0.12/kWh, which is close to the US national average.
- Click "Calculate" — View the daily, monthly, and yearly electricity cost along with energy consumption in kilowatt-hours (kWh).
Understanding Electricity Costs
Electricity is billed in kilowatt-hours (kWh). One kilowatt-hour equals the energy consumed by a 1,000-watt appliance running for one hour. Your monthly electricity bill is determined by the total kWh you consume multiplied by your utility's rate per kWh.
The formula for electricity cost is straightforward: Cost = (Watts × Hours ÷ 1,000) × Rate per kWh. For example, running a 100W light bulb for 10 hours uses 1 kWh. At the average US rate of $0.12/kWh, that costs just $0.12 — or about $3.60 per month if left on 10 hours every day.
The average US residential electricity rate is approximately $0.12 per kWh, but rates vary widely by state. Hawaii has the highest rates at around $0.33/kWh, followed by Connecticut and Massachusetts at $0.22-$0.25/kWh. Lower-cost states like Louisiana, Washington, and Idaho average $0.08-$0.10/kWh. Rates can also change based on time of use, seasonal demand, and your utility plan.
Several factors affect your electricity rate: your geographic location, the utility provider, time-of-use pricing (peak vs off-peak hours), tiered rate structures (higher rates once you exceed a baseline usage), and whether your state has a deregulated energy market that allows you to shop among providers.
Common Appliance Power Consumption
This table shows typical wattage, estimated daily use, and monthly cost at the US average rate of $0.12/kWh for common household appliances.
| Appliance | Typical Wattage | Daily Use (hours) | Monthly Cost ($0.12/kWh) |
|---|---|---|---|
| Central Air Conditioner | 3,500W | 8 | $100.80 |
| Electric Water Heater | 4,500W | 3 | $48.60 |
| Clothes Dryer | 5,000W | 1 | $18.00 |
| Space Heater | 1,500W | 8 | $43.20 |
| Window Air Conditioner | 1,200W | 8 | $34.56 |
| Electric Oven | 2,500W | 1 | $9.00 |
| Dishwasher | 1,800W | 1 | $6.48 |
| Washing Machine | 500W | 1 | $1.80 |
| Refrigerator | 150W | 24 | $12.96 |
| Microwave | 1,000W | 0.5 | $1.80 |
| Hair Dryer | 1,800W | 0.25 | $1.62 |
| Gaming PC | 500W | 4 | $7.20 |
| Desktop Computer | 200W | 8 | $5.76 |
| Laptop | 65W | 8 | $1.87 |
| LED TV (55") | 100W | 5 | $1.80 |
| LED Light Bulb | 10W | 8 | $0.29 |
| Ceiling Fan | 75W | 8 | $2.16 |
| Dehumidifier | 600W | 12 | $25.92 |
Tips to Reduce Your Electricity Bill
Here are practical ways to lower your energy costs without sacrificing comfort:
- Switch to LED bulbs — LED bulbs use about 75% less energy than incandescent bulbs and last 25 times longer. Replacing 10 incandescent bulbs with LEDs can save $100 or more per year.
- Use a programmable thermostat — Setting your thermostat back 7-10 degrees for 8 hours a day (while sleeping or at work) can save up to 10% on annual heating and cooling costs.
- Eliminate phantom loads — Many electronics draw power even when turned off. Use smart power strips or unplug chargers, game consoles, and small appliances when not in use. Phantom loads can account for 5-10% of your electricity bill.
- Upgrade to ENERGY STAR appliances — ENERGY STAR certified refrigerators, washers, and dishwashers use 10-50% less energy than standard models. An ENERGY STAR refrigerator saves roughly $35 per year compared to a 10-year-old model.
- Wash clothes in cold water — About 90% of the energy used by a washing machine goes to heating water. Switching to cold water for most loads can save $60-$100 per year.
- Air dry clothes when possible — A clothes dryer is one of the most energy-hungry appliances in your home at 5,000W. Air drying even half your loads can save $50-$75 annually.
- Seal air leaks and insulate — Gaps around windows, doors, and ductwork force your HVAC system to work harder. Weatherstripping and caulking are inexpensive fixes that can reduce heating and cooling costs by 10-20%.
- Use ceiling fans strategically — A ceiling fan uses only 75W compared to 1,200W for a window AC unit. In summer, run fans counterclockwise to create a wind-chill effect that lets you raise the thermostat by 4 degrees without losing comfort.
Frequently Asked Questions
Multiply the appliance's wattage by the number of hours you use it per day, then divide by 1,000 to convert to kilowatt-hours (kWh). Multiply the result by your electricity rate per kWh. The formula is: Daily Cost = (Watts × Hours/Day ÷ 1,000) × $/kWh. For example, a 1,500W space heater used 8 hours at $0.12/kWh costs (1,500 × 8 ÷ 1,000) × $0.12 = $1.44 per day.
A kilowatt-hour (kWh) is the standard unit of energy used for electricity billing. It represents the amount of energy consumed when a 1,000-watt appliance runs for one hour. For example, a 100W light bulb running for 10 hours uses 1 kWh (100W × 10h ÷ 1,000 = 1 kWh). Your electric bill shows total kWh consumed during the billing period.
The average US residential electricity rate is approximately $0.12 per kWh. However, rates vary significantly by state and region. Hawaii has the highest rates at around $0.33/kWh, while states like Louisiana and Washington average $0.08-$0.10/kWh. Check your most recent electricity bill for your exact rate, or look for the "energy charge" line item.
Your electricity rate is listed on your utility bill, usually as "price per kWh" or "energy charge." You can also find it on your utility provider's website under rate schedules. Be aware that some plans use tiered pricing (higher rates after a baseline), time-of-use pricing (different rates for peak and off-peak hours), or seasonal rates. For this calculator, use the rate that applies to your typical usage tier.
The biggest electricity consumers in a typical home are central air conditioning (3,000-5,000W), electric water heaters (4,500W), clothes dryers (5,000W), space heaters (1,500W), and electric ovens (2,500W). However, total cost depends on both wattage and hours of use. A refrigerator at 150W running 24 hours a day costs more per month than a 5,000W dryer used for 1 hour daily.
Yes, but many devices still draw standby power (also called phantom load or vampire power) even when turned off or in sleep mode. TVs, game consoles, cable boxes, and phone chargers can draw 5-25 watts continuously. Using a power strip and switching it off completely can eliminate these phantom loads and save $100-$200 per year for an average household.
A typical 1,500W space heater running 24 hours a day at the US average rate of $0.12/kWh costs $4.32 per day, $129.60 per month, or $1,576.80 per year. Running it only 8 hours per day reduces the cost to $1.44/day or $43.20/month. Space heaters are one of the most expensive appliances to operate, so use them in small, enclosed spaces and only when needed.