How much does 100 W cost for one hour?

At a rate of 31 per kWh, 100 ÷ 1,000 × 1 × 31 equals 3.1 currency units. Used daily for 30 days, it equals 93.

What is the electricity cost formula?

Divide watts by 1,000, then multiply by hours, days, and the electricity rate. Dividing watts by 1,000 converts power to kilowatts before calculating kWh.

What does a 1,000 W appliance cost for one hour daily?

At 31 per kWh for 30 days, 1 × 1 × 30 × 31 equals 930 currency units. Replace the rate with the figure from your plan.

Does the product wattage give an exact cost?

Products with thermostats or operating modes may not draw their rated maximum continuously. A measured average wattage will usually give a closer estimate.

Electricity Cost Calculator

Calculate daily and monthly electricity costs from watts and usage time.

Appliance guide

Power consumption (W)

Hours used per day

Number of days

Electricity rate (currency units/kWh)

Common values

Cost at 1 hour/day for 30 days (rate 31/kWh)

Power	Monthly energy	Monthly cost
10 W	0.3 kWh	9.3
50 W	1.5 kWh	46.5
65 W	1.95 kWh	60.45
100 W	3 kWh	93
300 W	9 kWh	279
600 W	18 kWh	558
1,000 W	30 kWh	930
1,200 W	36 kWh	1,116

About this tool

Enter an appliance's wattage, daily usage time, number of days, and electricity rate to estimate energy use and cost. Common appliance wattages are provided as rough guides; use the rating on your actual product for a more accurate result.

Energy use in kWh is watts divided by 1,000, multiplied by hours used. Cost is that energy use multiplied by the electricity rate and number of days.

Appliances with standby modes or thermostatic control do not necessarily draw their rated maximum continuously. Use a measured average wattage for a closer estimate.

The calculation excludes base charges, fuel adjustments, renewable-energy surcharges, and similar bill items. It estimates only the entered appliance usage.

FAQ

How much does 100 W cost for one hour?: At a rate of 31 per kWh, 100 ÷ 1,000 × 1 × 31 equals 3.1 currency units. Used daily for 30 days, it equals 93.
What is the electricity cost formula?: Divide watts by 1,000, then multiply by hours, days, and the electricity rate. Dividing watts by 1,000 converts power to kilowatts before calculating kWh.
What does a 1,000 W appliance cost for one hour daily?: At 31 per kWh for 30 days, 1 × 1 × 30 × 31 equals 930 currency units. Replace the rate with the figure from your plan.
Does the product wattage give an exact cost?: Products with thermostats or operating modes may not draw their rated maximum continuously. A measured average wattage will usually give a closer estimate.

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