Does anyone know how to determine electricity cost / wattage???

I am running a 1000 watt HPS at 12 hrs. and a 400 watt MH for 18 hrs. How can I determine how much this cost me per day to run?

power is measured in kilowatt hours (KWH). that is 1,000 watts of power running for one hour. your 1,000 watt hps is using 1 KWH for each hour it is on. Your 400 watt is using 0.4 KWH for each hour it is on. so: 1 KHW x 12 hours a day x 30 days a month = 360 kwh per month. 0.4 kwh x 18 hours a day x 30 days a month = 216 KHW per month. Your total power consumption for your lights is 576 KHW per month. Electricity rates vary in different places, so get you most recent power bill and find the rate, then multiply it by 576 and you have your cost. Where I live, Las Vegas, my rate is about 12 cents per KWH, so my cost would be $69.12 for that much power.

Here: https://www.rollitup.org/indoor-growing/3284-power-consumption-light-cost.html

lets say for example your electric company caharges 10 cents per kilowatt hr. 1 killowatt=1000 watts.... therefore If your running your 1000 watt hps 12 hours a day , its costing you $1.20 a day for your 1000 watter... now your 400 watt at 18 hours a day would be around 4 cents per killowatt hr so thats 72 cents a day for the 400 watter....This is IMO the easiest way to explain this....So at 10 cents per killowatt hr, your looking at $1.92 a day to run your equipment....