Electricity Cost Calculator
Calculate energy cost.
Electricity Calculator
Electricity Calculator: Energy Cost Estimator
Everything you need to know
About the Electricity Calculator
Electricity bills can be confusing. You know you're using power, but which appliances are the biggest culprits? Our electricity calculator breaks down your energy consumption appliance by appliance, helping you identify where your money is going and how to reduce your bill.
What you can calculate:
- Daily/monthly/yearly cost for any appliance
- Total household energy consumption
- Comparison: Old appliance vs. energy-efficient replacement
- kWh usage: Kilowatt-hours consumed
- Carbon footprint: CO₂ emissions from electricity use
How Electricity Costs Are Calculated
Basic Formula
Cost = (Wattage × Hours Used) ÷ 1000 × Price Per kWh
Where:
- Wattage: Power consumption in watts (listed on appliance label)
- Hours Used: Daily usage time
- Price Per kWh: Your utility rate (check your electric bill)
Example: Refrigerator
- Wattage: 150 watts
- Runs: 24 hours/day (compressor cycles on/off, but averages ~8 hours active)
- Rate: $0.14/kWh
Daily cost = (150 × 8) ÷ 1000 × 0.14 = $0.17/day Monthly cost = $0.17 × 30 = $5.10/month Yearly cost = $5.10 × 12 = $61.20/year
Common Appliance Energy Costs
| Appliance | Wattage | Daily Hours | Monthly Cost* |
|---|---|---|---|
| Central AC (3-ton) | 3,500 | 8 (summer) | $117.60 |
| Space heater | 1,500 | 6 (winter) | $37.80 |
| Water heater | 4,500 | 3 | $56.70 |
| Clothes dryer | 3,000 | 1 | $12.60 |
| Washing machine | 500 | 1 | $2.10 |
| Dishwasher | 1,800 | 1.5 | $11.34 |
| Refrigerator | 150 | 24 (8 active) | $5.04 |
| LED TV (55") | 80 | 5 | $1.68 |
| Desktop computer | 200 | 8 | $6.72 |
| Laptop | 60 | 8 | $2.02 |
| Incandescent bulb (60W) | 60 | 5 | $1.26 |
| LED bulb (eq. 60W) | 10 | 5 | $0.21 |
| Ceiling fan | 75 | 8 | $2.52 |
| Microwave | 1,100 | 0.25 | $1.16 |
| Coffee maker | 1,000 | 0.5 | $2.10 |
*At $0.14/kWh; rates vary by location and season
Understanding Your Electric Bill
| Term | Meaning | Example |
|---|---|---|
| kWh | Kilowatt-hour = 1,000 watts used for 1 hour | Running a 100W bulb for 10 hours = 1 kWh |
| Rate | Cost per kWh | $0.12 - $0.30+ depending on location |
| Base charge | Fixed monthly fee | $10-20/month |
| Tiered pricing | Higher rates after using certain kWh | First 500 kWh @ $0.12, next 500 @ $0.15 |
| Time-of-use | Different rates by time of day | Peak hours @ $0.25, off-peak @ $0.10 |
| Delivery charges | Grid maintenance fees | Separate from generation charges |
Average Monthly Electricity Usage by Household
| Household Size | Average kWh/Month | Estimated Bill* |
|---|---|---|
| 1 person (apartment) | 300-500 | $42-70 |
| 2 people (small home) | 600-900 | $84-126 |
| 4 people (medium home) | 1,000-1,500 | $140-210 |
| 4+ people (large home) | 1,500-2,500+ | $210-350+ |
*At $0.14/kWh
Tips to Reduce Your Electricity Bill
- Switch to LED bulbs: Use 75-90% less energy than incandescent
- Unplug phantom loads: Devices in standby mode can cost $100+/year
- Use a programmable thermostat: Save 10-15% on heating/cooling
- Air dry clothes: Dryers are among the most expensive appliances
- Wash clothes in cold water: Heating water accounts for 90% of washing machine energy
- Seal air leaks: Poor insulation can increase HVAC costs by 20%
- Use smart power strips: Cut power to devices when not in use
- Maintain appliances: Clean AC filters and refrigerator coils regularly
- Run dishwasher and laundry at full load: More efficient per item
- Consider solar: Rooftop solar can eliminate most or all of your bill
Calculating Energy Savings
Example: Replacing 20 incandescent bulbs (60W) with LEDs (10W)
- Old: 20 × 60W × 5 hours × 30 days = 180 kWh/month
- New: 20 × 10W × 5 hours × 30 days = 30 kWh/month
- Savings: 150 kWh/month = $21/month = $252/year
- LED cost: $3/bulb × 20 = $60
- Payback period: ~3 months
Frequently Asked Questions
What's the difference between watts and kilowatt-hours?
Watts (W) measure power (rate of use). Kilowatt-hours (kWh) measure energy (total used over time). A 1,000W appliance running for 1 hour uses 1 kWh.
Why is my electric bill so high in summer?
Air conditioning is typically the largest energy consumer. A central AC unit can use 3,000-5,000 watts and run 8+ hours daily in hot climates.
Do appliances use electricity when turned off?
Yes. "Phantom load" or "vampire power" from devices in standby mode can account for 5-10% of your bill. Use smart power strips to eliminate this.
How much does it cost to charge an electric vehicle?
A typical EV gets 3-4 miles per kWh. At $0.14/kWh, driving 12,000 miles/year costs approximately $420-560/year in electricity—much less than gas.
Is it cheaper to run appliances at night?
If your utility offers time-of-use pricing, yes. Off-peak rates (usually 9 PM - 7 AM) can be 50% cheaper than peak rates.