Electricity Bill Estimator
Estimate monthly electricity bill from appliance wattage, daily usage hours, and kWh rate.
Add multiple devices to see which ones cost the most to run.
Estimated Monthly Bill
Monthly kWh = (Watts × Hours per Day × 30) / 1000
Monthly Cost = Monthly kWh × Rate per kWh
This calculator estimates your monthly electricity bill based on total wattage, daily usage hours, and your electricity rate. A kilowatt-hour (kWh) is the standard billing unit – it means using 1,000 watts for one hour.
What the variables mean:
- Total Watts – the combined wattage of all appliances running (check labels or manuals)
- Hours per Day – the average number of hours these appliances run daily
- Rate ($/kWh) – your electricity price, found on your utility bill (US average is about $0.12-0.16/kWh)
Common appliance wattages:
| Appliance | Typical Watts | Hours/Day | Monthly Cost ($0.13/kWh) |
|---|---|---|---|
| Refrigerator | 150W | 8 | $4.68 |
| Air conditioner | 1,500W | 8 | $46.80 |
| LED bulb | 10W | 5 | $0.20 |
| Television | 100W | 4 | $1.56 |
| Washing machine | 500W | 1 | $1.95 |
| Desktop computer | 200W | 6 | $4.68 |
| Space heater | 1,500W | 4 | $23.40 |
| Microwave | 1,000W | 0.5 | $1.95 |
Practical example: If your home uses 3,000W of appliances for an average of 8 hours daily at $0.13/kWh: Monthly kWh = (3,000 × 8 × 30) / 1,000 = 720 kWh. Monthly cost = 720 × $0.13 = $93.60. Annual cost = $1,123.20.
Tips:
- Not all appliances run constantly. A fridge cycles on and off, so it may draw 150W but only runs about 8 hours total per day.
- The biggest energy consumers in most homes are heating, cooling, and water heating.
- Switching from incandescent bulbs (60W) to LED (10W) can reduce lighting costs by over 80%.
- The calculator shows daily, monthly, and annual costs for complete budgeting.