Watts measure instantaneous power. kWh measures total energy consumed. A 100W bulb running 10 hours uses 1 kWh.
kWh = Watts × Hours ÷ 1000. Convert watts to kW first, then multiply by time.
Multiply kWh by your electricity rate to estimate cost.
Electricity billing, appliance efficiency comparison, solar sizing.
1 kWh = 1,000 watt-hours. It costs about $0.10–$0.30 depending on region.
Convert power to energy.
Divide watts by 1000 to get kW, then multiply by hours for kWh.
3 simple steps.
Check the appliance label for watts. LED bulb: 10W, AC: 1500W, Heater: 2000W.
How many hours per day/month does the appliance run?
Watts × Hours ÷ 1000 = kWh. Multiply by rate for cost.
Daily energy consumption for common appliances.
| Appliance | Watts | 8 hr kWh | 24 hr kWh | Monthly kWh |
|---|---|---|---|---|
| 10 | LED Bulb | 0.08 | 0.24 | 7.2 |
| 60 | Incandescent | 0.48 | 1.44 | 43.2 |
| 150 | TV | 1.20 | 3.60 | 108.0 |
| 1000 | Space Heater | 8.00 | 24.00 | 720.0 |
| 1500 | Hair Dryer | 12.00 | 36.00 | 1,080.0 |
| 3500 | AC Unit | 28.00 | 84.00 | 2,520.0 |
Real-world energy consumption.
10 W bulb for 10 hours/day × 30 days:
10 × 300 ÷ 1000 = 3 kWh/month ($0.36)
1,500 W AC for 8 hours/day × 30 days:
1500 × 240 ÷ 1000 = 360 kWh/month ($43.20)
300 W PC for 12 hours/day × 30 days:
300 × 360 ÷ 1000 = 108 kWh/month ($12.96)
25 free conversion tools — each with its own unique calculator, interactive visuals, and detailed explanations.
Converter for kva-to-watts
Converter for kva-to-mw
Converter for kva-to-amps
Converter for kva-to-kwh
Converter for kva-to-hp
Converter for kva-to-va
Converter for kva-to-btu
Converter for kva-to-gw
Converter for kva-to-kw-3-phase
Converter for kva-to-joule
Converter for kva-to-kv
Converter for kva-to-ka
Converter for kva-to-mbh
Converter for kva-to-mwh
Converter for kva-to-mva
Converter for kva-to-rpm
Converter for va-to-v
Converter for kw-to-kwh
Converter for power-factor-calculator
Converter for transformer-kva-calculator
Converter for generator-size-calculator
Converter for kva-to-kvar
Converter for kvar-calculator
Converter for watts-to-kwh
Converter for voltage-drop-calculator
Common questions about watts to kWh conversion.
1 kWh = 1,000 watt-hours. A 1,000W device running 1 hour = 1 kWh.
kWh = Watts × Hours ÷ 1000. Then multiply kWh by your rate (check your utility bill).
A modern fridge uses about 100–400 kWh per year, or 8–33 kWh/month.
HVAC (heating/cooling), water heaters, and electric dryers are the biggest consumers.
Use LED bulbs, Energy Star appliances, smart thermostats, and turn off unused devices.