⚡Electricity Calculator
Estimate electricity usage and cost for any appliance. Choose from 24 preset appliances or enter custom wattage. Set usage capacity, hours of use per day/week/month, and electricity price to see hourly, daily, monthly, and annual energy consumption and cost.
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Monthly Cost
$36.52
Cost Breakdown by Period
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Electricity Calculator: How Much Does It Cost to Run Any Appliance?
To calculate electricity cost: Cost = Watts ÷ 1,000 × Hours × Price per kWh. A 1,000W microwave used 30 min/day = 0.5 kWh/day = 15 kWh/month. At $0.15/kWh → $2.25/month. A central air conditioner at 3,500W running 8 hours/day = 28 kWh/day = $4.20/day at $0.15/kWh.
Formula: kWh = Watts ÷ 1,000 × Hours | Monthly cost = kWh × Days × $/kWh
| Appliance | Typical watts | $/month (8h/day) |
|---|---|---|
| Space heater | 1,500 W | ~$54 |
| Refrigerator | 150 W (40% avg) | ~$6.48/month |
| LED bulb (60W equiv) | 10 W | ~$0.36 |
Understanding the electricity consumption of individual appliances is the first step to reducing energy bills. Major users are typically heating and cooling (air conditioners, space heaters, water heaters), clothes dryers, and EV charging. Small appliances and lighting are minor contributors to total usage despite common perception — switching to LED bulbs saves money but rarely dominates the bill.
Reading Your Electricity Bill
Utility bills charge by kilowatt-hour (kWh). The average US household uses approximately 900 kWh per month at an average price of ~$0.15/kWh, totaling about $135/month. Rates vary significantly: Hawaii averages $0.35/kWh; Louisiana, Oklahoma, and Arkansas average $0.09–$0.10/kWh. Most utilities offer time-of-use (TOU) rates where electricity is cheaper at off-peak hours (nights and weekends) — relevant for scheduling EV charging, dishwashers, and laundry.
Reducing Electricity Costs
The highest-impact changes are typically: upgrading from window to central AC (or adding insulation), switching to an electric heat pump water heater (3–4× more efficient than resistance heating), using LED lighting throughout (90% less energy than incandescent), and charging EVs at night on cheaper off-peak rates. Smart power strips eliminate phantom loads from electronics in standby mode, which can account for 5–10% of home electricity use.
Frequently Asked Questions
How do I calculate electricity cost for an appliance?
Cost = (Watts ÷ 1,000) × Hours × Price per kWh. Step 1: Find the appliance's wattage (on the label, manual, or use our presets). Step 2: Estimate daily hours of use. Step 3: Multiply by your electricity rate (check your bill — typically $0.10–$0.35/kWh in the US). Example: 1,500W space heater × 8 hours/day = 12 kWh/day. At $0.15/kWh = $1.80/day = $54/month. Annual cost = 12 × 365 × $0.15 = $657/year.
What uses the most electricity in a home?
Heating and cooling (HVAC) accounts for 45–50% of average US home electricity use — by far the largest category. Water heating is second at ~18%. Appliances (refrigerator, washer, dryer, dishwasher) account for ~15%. Lighting uses about 9% — dramatically lower since the shift to LEDs. Electronics (TVs, computers, gaming) account for ~4%. The single most electricity-intensive items are: central air conditioner (~3,500W), electric water heater (~4,000W), clothes dryer (~5,000W), and EV charger (~7,200W). Focusing on these big users has the most impact on your bill.
How do I find out how many watts an appliance uses?
Check the manufacturer's label (usually on the back or bottom) for "rated power" in watts or kilowatts. Check the user manual or product specifications online — search the model number plus "watt" or "power consumption." Use a smart plug or kill-a-watt meter to measure actual power draw, which may be less than the rated maximum. Note that some appliances (refrigerators, air conditioners) cycle on and off, so the average draw is a fraction of the rated power. This calculator includes the "capacity %" field to account for partial loading.
How many kWh does a refrigerator use per month?
A modern Energy Star refrigerator typically uses 400–600 kWh per year, or about 35–50 kWh per month. At $0.15/kWh, that is $5–$7.50 per month. Older (pre-2000) refrigerators may use 2–3 times more. The rated wattage (usually 100–200W) is the peak draw when the compressor runs; actual average draw is typically 30–40% of rated wattage since the compressor cycles on and off. Refrigerators run 24 hours/day, so even moderate consumption adds up. Size, age, and thermostat settings all affect consumption significantly.