kW to kWh Calculator

Q: How many kWh is 1 kW?

1 kW running for 1 hour uses 1 kWh. Running for 5 hours, it uses 5 kWh.

Q: How do I convert watts to kWh?

Divide watts by 1,000 to get kW, then multiply by hours. A 1,500 W heater for 4 hours: 1.5 × 4 = 6 kWh.

Q: How much does it cost to run a 2 kW heater for 5 hours?

2 × 5 = 10 kWh. At $0.16 per kWh that is $1.60; at $0.30 per kWh it is $3.00.

Q: Is kW per hour the same as kWh?

No. "kW per hour" would describe how fast power changes. A kilowatt-hour is kW multiplied by hours: energy, not a rate.

Q: How many kWh does a 5 kW solar system produce?

kWh = 5 kW × peak sun hours. With 4 peak sun hours a day it produces roughly 20 kWh a day before system losses, which commonly reduce output by 10–20%.

Convert kilowatts (kW) to kilowatt-hours (kWh) by multiplying by hours of use: kWh = kW × h. Estimate energy use and electricity cost for any appliance.

⚡ POWER

🕐 TIME

hours

ENERGY

24 kWh

MONTHLY

720 kWh

EST. DAILY COST

$3.84

FORMULA

kWh = kW × h

kW to kWh — Usage Table

kW	1 hr	4 hrs	8 hrs	24 hrs	Cost/Day
0.5 kW	0.5	2	4	12	$1.92
1 kW	1	4	8	24	$3.84
1.5 kW	1.5	6	12	36	$5.76
2 kW	2	8	16	48	$7.68
3 kW	3	12	24	72	$11.52
5 kW	5	20	40	120	$19.2
7.5 kW	7.5	30	60	180	$28.8
10 kW	10	40	80	240	$38.4
15 kW	15	60	120	360	$57.6
20 kW	20	80	160	480	$76.8

💡 How to Convert kW to kWh

To convert kW to kWh, multiply the power in kilowatts by the number of hours it runs. The result is the energy used, the figure your electricity bill charges for. Multiply kWh by your price per kWh to estimate cost.

kW to kWh formula

kWh = kW × hours · Cost = kWh × price per kWh

Example: a 3 kW air conditioner for 8 hours → 3 × 8 = 24 kWh; at $0.16/kWh that is $3.84

The calculator uses $0.16 per kWh as an example rate. Replace it mentally with the rate on your own bill, since prices vary widely by country, utility and time of day.

Worked examples

Oven: 2.4 kW for 1.5 hours = 3.6 kWh.
EV home charger: 7 kW for 4 hours = 28 kWh.
Watts first: a 100 W TV is 0.1 kW, so 10 hours = 1 kWh. Divide watts by 1,000 to get kW.

kW to kWh table (with cost at $0.16/kWh)

Power (kW)	Hours	Energy (kWh)	Cost
0.1	10	1	$0.16
0.5	8	4	$0.64
1	1	1	$0.16
1.5	6	9	$1.44
2	3	6	$0.96
2.4	1.5	3.6	$0.58
3	8	24	$3.84
3.5	8	28	$4.48
7	4	28	$4.48
11	6	66	$10.56

Getting accurate estimates

Use actual power, not the label maximum. Many appliances cycle on and off (fridges, air conditioners, ovens with thermostats), so average draw is below the rated kW.
Measure if you can. A plug-in energy meter or a smart meter app shows the real kWh used.
Count standby. Small loads left on 24 hours a day add up: 10 W × 24 h × 365 days = 87.6 kWh a year.

Related conversions: kWh to kW · watts to kWh · Ah to kWh

kWh = kW × hours. A 3 kW appliance running 8 hours uses 24 kWh.