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Electricity Cost Calculator

How much does it cost to run an appliance? Calculate the electricity cost of any device, estimate your whole home bill, or compare old vs energy-efficient replacements. Works with any currency.

All amounts displayed in selected currency
Select a preset or choose Custom
W
Power consumption in watts (check the label)
hrs
Average daily usage hours
$/kWh
Your electricity price per kilowatt-hour
Estimates only. Actual costs depend on appliance efficiency, usage patterns, and local rates.

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How to Use This Calculator

Tab "Single Appliance"

Select an appliance from the dropdown (or choose Custom and enter your own wattage). Set the hours per day you use it and your electricity rate per kWh. The calculator shows daily, monthly, and annual electricity costs plus energy consumption in kWh.

Tab "Whole Home"

Add up to 10 appliances with their wattage and daily usage hours. The calculator totals your home electricity estimate and ranks appliances from most to least expensive, so you can see where your money goes.

Tab "Compare Appliances"

Enter the wattage of your old appliance and a new energy-efficient replacement, plus daily hours, electricity rate, and the new appliance price. The result shows annual savings and payback period — how long until the new appliance pays for itself in electricity savings.

The Formulas

Energy consumption (kWh):
kWh per day = Watts × Hours per day / 1,000

Electricity cost:
Daily cost = kWh per day × Rate per kWh
Monthly cost = Daily cost × 30.44
Annual cost = Daily cost × 365

Efficiency comparison:
Annual savings = Old annual cost − New annual cost
Payback period = New appliance price / Annual savings

All calculations are universal. No country-specific rates or tariffs are applied. Enter your own electricity rate from your utility bill.

Worked Examples

Example 1 — Space heater: $54.78/month

A 1,500-watt space heater runs 8 hours per day during winter at an electricity rate of $0.15 per kWh.

Wattage1,500 W
Usage8 hours/day
Rate$0.15/kWh
kWh/day1,500 × 8 / 1,000 = 12 kWh
Daily cost12 × $0.15 = $1.80
Monthly cost$1.80 × 30.44 = $54.78
Annual cost$1.80 × 365 = $657.00

Space heaters are one of the most expensive appliances to run. Even a few hours per day adds up quickly over a winter season.

Example 2 — EV charging at home: $78.73/month

A Level 2 EV charger draws 7,200 watts and charges for 3 hours per day at $0.12 per kWh (off-peak rate).

Wattage7,200 W
Usage3 hours/day
Rate$0.12/kWh
kWh/day7,200 × 3 / 1,000 = 21.6 kWh
Daily cost21.6 × $0.12 = $2.59
Monthly cost$2.59 × 30.44 = $78.73
Annual cost$2.59 × 365 = $945.54

Home EV charging is significantly cheaper than public charging stations or gasoline. Using off-peak rates can reduce costs further.

Example 3 — Old vs new fridge: 9.5-year payback

An old refrigerator draws 200 watts. A new energy-efficient model draws only 80 watts. Both run 24 hours a day at $0.15/kWh. The new fridge costs $600.

Old fridge200 W × 24 hrs = 4.8 kWh/day
Old annual cost4.8 × $0.15 × 365 = $262.80
New fridge80 W × 24 hrs = 1.92 kWh/day
New annual cost1.92 × $0.15 × 365 = $105.12
Annual savings$262.80 − $105.12 = $157.68
Payback period$600 / $157.68 = 3.8 years

The new fridge pays for itself in under 4 years through electricity savings alone. Over a 15-year lifespan, the total savings exceed $1,700.

Understanding Electricity Costs

What Is a Kilowatt-Hour (kWh)?

A kilowatt-hour is the standard unit of electricity billing. It represents using 1,000 watts of power for one hour. A 100-watt light bulb running for 10 hours uses 1 kWh. Your electricity bill charges you per kWh consumed.

Why Wattage Alone Does Not Tell the Full Story

A 7,200W EV charger sounds expensive, but if it only runs 3 hours a day, it uses 21.6 kWh. A 150W fridge sounds cheap, but running 24/7 it uses 3.6 kWh daily. Over a month, the fridge costs about 60% of the charger despite being 48 times lower wattage. Usage hours matter as much as wattage.

How to Find Your Electricity Rate

Check your electricity bill for the rate per kWh. It is usually listed under "supply charges" or "energy charges." Common rates range from $0.08 to $0.30 per kWh depending on your country and provider. Some utilities offer time-of-use rates where off-peak hours are cheaper.

When Does Upgrading Make Sense?

Use the Compare tab to find the payback period. If the payback is shorter than the expected lifespan of the new appliance, the upgrade saves money over time. Refrigerators, air conditioners, and water heaters often have the best payback because they run the most hours per day.

Frequently Asked Questions

Multiply the wattage by hours of daily use, divide by 1,000 to get kWh, then multiply by your rate per kWh. For monthly cost, multiply the daily cost by 30.44. For example, a 100W TV watched 5 hours a day at $0.15/kWh costs $0.075/day or $2.28/month.
The biggest consumers are typically HVAC systems (air conditioners, space heaters), water heaters, clothes dryers, ovens, and EV chargers. Appliances that run continuously (refrigerators, freezers) also contribute significantly despite their lower wattage. Use the Whole Home tab to rank your specific appliances.
A typical 1,500W space heater running 24 hours at $0.15/kWh costs $5.40/day or $164.38/month. Running it 8 hours costs $1.80/day or $54.78/month. Space heaters are among the most expensive appliances to operate.
Start by identifying your most expensive appliances using the Whole Home tab. Common strategies include: upgrading to energy-efficient models (especially fridges and AC units), using appliances during off-peak hours if your utility offers time-of-use rates, reducing usage hours, switching to LED lighting, and improving home insulation to reduce heating/cooling needs.
No. This is a universal electricity cost calculator that works with any currency and rate. Enter your own electricity rate from your utility bill. For country-specific energy calculators, see the country links below the calculator for UK, Germany, New Zealand, and more.

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