Watts to kWh Calculator
Convert watts to kilowatt-hours (kWh) to calculate energy consumption. Enter wattage and hours of use to see how much electricity your appliances consume and what it costs based on US electricity rates.
ENERGY CONSUMED
12 kWh
KILOWATTS
1.5 kW
EST. COST (US AVG)
$1.92
FORMULA
E = (W ร h) / 1000
Watts to kWh โ Daily Energy Usage
| Device (Watts) | 1 hr | 4 hrs | 8 hrs | 24 hrs | Cost/Day |
|---|---|---|---|---|---|
| 60 W | 0.06 kWh | 0.24 kWh | 0.48 kWh | 1.4 kWh | $0.23 |
| 100 W | 0.1 kWh | 0.4 kWh | 0.8 kWh | 2.4 kWh | $0.38 |
| 150 W | 0.15 kWh | 0.6 kWh | 1.2 kWh | 3.6 kWh | $0.58 |
| 200 W | 0.2 kWh | 0.8 kWh | 1.6 kWh | 4.8 kWh | $0.77 |
| 500 W | 0.5 kWh | 2 kWh | 4 kWh | 12 kWh | $1.92 |
| 750 W | 0.75 kWh | 3 kWh | 6 kWh | 18 kWh | $2.88 |
| 1,000 W | 1 kWh | 4 kWh | 8 kWh | 24 kWh | $3.84 |
| 1,500 W | 1.5 kWh | 6 kWh | 12 kWh | 36 kWh | $5.76 |
| 2,000 W | 2 kWh | 8 kWh | 16 kWh | 48 kWh | $7.68 |
| 3,000 W | 3 kWh | 12 kWh | 24 kWh | 72 kWh | $11.52 |
| 5,000 W | 5 kWh | 20 kWh | 40 kWh | 120 kWh | $19.2 |
| 10,000 W | 10 kWh | 40 kWh | 80 kWh | 240 kWh | $38.4 |
* Cost estimated at US national average of $0.16/kWh (EIA, 2024). Actual rates vary by state.
๐ก How to Convert Watts to Kilowatt-Hours (kWh)
Kilowatt-hours (kWh) is the standard unit for measuring electrical energy consumption. It's what appears on your electricity bill. Converting watts to kWh tells you how much energy a device consumes over a given period.
Watts to kWh Formula
Where:
E = Energy in kilowatt-hours (kWh)
P = Power in watts (W)
t = Time in hours (h)
Kilowatt-hours measure energy (watts ร time), while watts measure power (the rate of energy use). A 100-watt bulb running for 10 hours consumes 1 kWh.
Example: Running a Space Heater
E = (1,500 ร 8) / 1,000 = 12 kWh/day
Monthly = 12 ร 30 = 360 kWh/month
Cost = 360 ร $0.16 = $57.60/month
US Electricity Cost by State (2024 Average)
The US national average is approximately $0.16/kWh, but rates vary significantly by state:
| State | Rate ($/kWh) | State | Rate ($/kWh) |
|---|---|---|---|
| Hawaii | $0.43 | Texas | $0.14 |
| Connecticut | $0.29 | Florida | $0.14 |
| Massachusetts | $0.28 | North Carolina | $0.12 |
| California | $0.27 | Idaho | $0.10 |
| New York | $0.22 | Louisiana | $0.10 |
Source: U.S. Energy Information Administration (EIA), 2024 data
Common Appliance Energy Use
| Appliance | Watts | Daily Use | kWh/Day | Cost/Month |
|---|---|---|---|---|
| LED Bulb | 10 W | 8 hrs | 0.08 | $0.38 |
| Laptop | 65 W | 8 hrs | 0.52 | $2.50 |
| Refrigerator | 150 W | 24 hrs | 3.60 | $17.28 |
| TV (55 inch) | 100 W | 5 hrs | 0.50 | $2.40 |
| Space Heater | 1,500 W | 8 hrs | 12.00 | $57.60 |
| Central AC | 3,500 W | 8 hrs | 28.00 | $134.40 |
| Electric Dryer | 5,000 W | 1 hr | 5.00 | $24.00 |
* Cost at US average of $0.16/kWh
US Average Household Electricity Use
According to the U.S. Energy Information Administration (EIA), the average US household consumes approximately 886 kWh per month (10,632 kWh/year), costing about $142/month at the national average rate.
References
- U.S. Energy Information Administration (EIA) โ Electricity Data, 2024
- ENERGY STAR โ Energy-Saving Guidelines