kWh to Watts Converter
Convert between kilowatt-hours (kWh) and watts instantly. Understand the difference between energy and power with our free calculator.
Quick Answer: kWh to Watts Formula
Example: 2 kWh used over 4 hours = (2 × 1,000) ÷ 4 = 500 watts
kWh ↔ Watts Converter
Convert between kilowatt-hours (energy) and watts (power)
Conversion Results
Quick Reference
Watts vs. Kilowatt-Hours: What's the Difference?
Understanding the key distinction between power and energy
Watts (W)
- • Measures power (rate of energy use)
- • Like your car's speedometer
- • Shows how fast you're using energy right now
- • Listed on appliance labels
Kilowatt-Hours (kWh)
- • Measures energy (total consumption)
- • Like your car's odometer
- • Shows total energy used over time
- • What you pay for on your electric bill
Real-World Analogy
Imagine filling a bathtub. Watts are like the water flow rate (gallons per minute)—how fast water comes out of the faucet. Kilowatt-hours are like the total water used (gallons)—how much water ends up in the tub. You can fill the tub slowly (low watts for many hours) or quickly (high watts for fewer hours), but either way you'll use the same total amount (kWh).
Common Appliance Power Usage
How watts translate to daily kWh for typical household appliances
| Appliance | Watts | Hours/Day | kWh/Day |
|---|---|---|---|
| LED Bulb | 10 | 5 | 0.05 |
| Laptop | 50 | 8 | 0.4 |
| Desktop Computer | 200 | 8 | 1.6 |
| Refrigerator | 150 | 24 | 3.6 |
| Window A/C | 1,200 | 8 | 9.6 |
| Central A/C | 3,500 | 6 | 21 |
| Electric Heater | 1,500 | 6 | 9 |
| Washing Machine | 500 | 1 | 0.5 |
| Electric Dryer | 3,000 | 1 | 3 |
| Microwave | 1,000 | 0.25 | 0.25 |
* Daily kWh = (Watts × Hours) ÷ 1,000. Actual usage varies by appliance efficiency and usage patterns.
Electricity Unit Conversions
Quick reference for common energy and power unit conversions
Kilowatt-hours to watt-hours
Kilowatts to watts
Megawatt-hours to kilowatt-hours
Gigawatt-hours to kilowatt-hours
How to Calculate kWh from Watts
Step-by-step guide to calculating your electricity usage
Find the wattage
Look for the watts (W) on your appliance label. It might say "100W" or "1500 watts". If you only see amps and volts, multiply them: Watts = Volts × Amps.
Estimate daily usage hours
How many hours per day does the appliance run? A refrigerator runs ~8 hours of actual compressor time. A TV might run 4-6 hours. A light bulb depends on your habits.
Calculate daily kWh
Use the formula: kWh = (Watts × Hours) ÷ 1,000
Example: 1,500W heater × 4 hours ÷ 1,000 = 6 kWh per day
Calculate the cost
Multiply kWh by your electricity rate. At 15¢/kWh: 6 kWh × $0.15 = $0.90 per day or about $27/month.
Frequently Asked Questions
Common questions about kWh and watts
How many watts are in a kilowatt-hour?
A kilowatt-hour (kWh) measures energy, while a watt measures power—they're different units. However, 1 kWh equals 1,000 watt-hours. To find watts from kWh, you need to know the time: Watts = (kWh × 1,000) ÷ hours. For example, 1 kWh used over 1 hour equals 1,000 watts.
How do I convert kWh to watts?
To convert kWh to watts: 1) Divide kWh by the number of hours, 2) Multiply by 1,000. Formula: Watts = (kWh ÷ hours) × 1,000. Example: If an appliance uses 2 kWh over 4 hours, that's (2 ÷ 4) × 1,000 = 500 watts.
What is the difference between kWh and watts?
Watts (W) measure power—the rate of energy use at any moment. Kilowatt-hours (kWh) measure energy—the total amount used over time. Think of it like driving: watts are your speed (miles per hour), while kWh is the total distance traveled. Your electricity bill charges for kWh (energy consumed), not watts (power drawn).
How do I convert watts to kWh?
To convert watts to kWh: 1) Multiply watts by hours of use, 2) Divide by 1,000. Formula: kWh = (Watts × hours) ÷ 1,000. Example: A 100-watt bulb running for 10 hours uses (100 × 10) ÷ 1,000 = 1 kWh.
What does 1 kWh of electricity look like?
1 kWh can power: a 100-watt bulb for 10 hours, a 1,000-watt microwave for 1 hour, a laptop for 5-8 hours, a TV for 3-4 hours, or a refrigerator for about 3-4 hours. At average U.S. electricity rates (~15¢/kWh), 1 kWh costs about 15 cents.
How many kWh does a 1,500 watt heater use per hour?
A 1,500-watt heater uses 1.5 kWh per hour (1,500 ÷ 1,000 = 1.5). Running it for 8 hours uses 12 kWh. At 15¢/kWh, that costs $1.80 per day or about $54 per month if used 8 hours daily.
What is the formula for kilowatt-hours?
The kWh formula is: kWh = (Watts × Hours) ÷ 1,000. Alternatively: kWh = Kilowatts × Hours. To convert back: Watts = (kWh × 1,000) ÷ Hours. These formulas work because 1 kilowatt = 1,000 watts.
How do I calculate my electricity cost from watts?
To calculate cost: 1) Find your appliance wattage (on the label), 2) Estimate daily hours of use, 3) Calculate kWh: (Watts × hours) ÷ 1,000, 4) Multiply by your electricity rate. Example: 1,000W appliance × 5 hours ÷ 1,000 = 5 kWh × $0.15 = $0.75/day.
Find the Best Electricity Rate for Your Usage
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