Appliance electricity cost
Multiply electricity use in kilowatt-hours by your price per kilowatt-hour. Start with annual kWh when you have it, annualize a representative meter reading when you do not, and use watts multiplied by runtime only as a fallback.
Direct answer
kWh × $/kWh = electricity cost
An appliance using 600 kWh a year at $0.18 per kWh costs 600 × $0.18 = $108 a year. That is a $9.00 average month or about $0.30 a day. Convert cents to dollars before multiplying: 18 cents is $0.18. If your bill is not a simple flat rate, first determine which electricity rate to use for an appliance calculation.
Choose your input
Annual kWh requires the fewest assumptions. A meter reading can reflect your household more closely, but a short reading must represent normal use before you scale it to a year. Rated watts and estimated runtime introduce the most guesswork.
1 · Best direct input
Find the appliance's annual electricity consumption, then multiply it by your rate. A yellow label states annual kWh under standardized test assumptions; our EnergyGuide label walkthrough explains where to find it and why the printed dollar estimate is not your local result.
Formula: annual kWh × rate in dollars per kWh = annual cost.
2 · Household-specific input
If you already have a safe, compatible meter reading, divide measured kWh by the number of measured days. Multiply that daily use by 365, then multiply by your rate. Include ordinary cycles, settings, and standby time in the measurement period.
Formula: measured kWh ÷ measured days × 365 × rate = annual cost.
3 · Estimation fallback
Divide watts by 1,000 to get kilowatts, multiply by hours of use, and then multiply by your rate. Use the time the appliance actually draws that wattage—not merely the time it stays plugged in.
Formula: watts ÷ 1,000 × hours used × rate = cost.
Important limit
Refrigerators, air conditioners, dehumidifiers, and other thermostatically controlled equipment cycle on and off. Conditions and settings change how long the active cycle runs. Multiplying rated watts by every hour the appliance is switched on can therefore differ substantially from actual kWh. Prefer annual or representative measured kWh for a cycling load.
Worked example 1
Assume the annual-use figure is 600 kWh and the household rate is $0.18 per kWh. The yearly calculation comes first; monthly and daily figures are averages.
| Period | Electricity use | Transparent arithmetic | Cost |
|---|---|---|---|
| Daily average | 600 ÷ 365 = 1.644 kWh | 1.644 × $0.18 | $0.30 |
| Monthly average | 600 ÷ 12 = 50 kWh | 50 × $0.18 | $9.00 |
| Year | 600 kWh | 600 × $0.18 | $108.00 |
Daily cost is rounded to the nearest cent. An actual month's use can differ from the annual average because appliance use, weather, and the number of days in a month vary.
Worked example 2
This example uses the same $0.18 rate. It assumes the eight-day reading represents ordinary use; unusual weather, guests, travel, or settings would weaken that assumption.
9.6 kWh ÷ 8 days = 1.2 kWh/day. Then 1.2 × $0.18 = $0.216, rounded to $0.22.
1.2 × (365 ÷ 12) = 36.5 kWh/month. Then 36.5 × $0.18 = $6.57.
1.2 × 365 = 438 kWh/year. Then 438 × $0.18 = $78.84.
Worked example 3
Convert 1,200 watts to 1.2 kilowatts and 45 minutes to 0.75 hour. This path assumes the appliance draws 1,200 watts for the full 45 minutes each day.
1,200 ÷ 1,000 × 0.75 = 0.9 kWh/day. Then 0.9 × $0.18 = $0.162, rounded to $0.16.
0.9 × (365 ÷ 12) = 27.375 kWh/month. Then 27.375 × $0.18 = $4.9275, rounded to $4.93.
0.9 × 365 = 328.5 kWh/year. Then 328.5 × $0.18 = $59.13.
Next decision
Once you have annual kWh for the appliance you own and a possible replacement, add the purchase price, rebate, and expected ownership period. The result separates a lower power bill from the larger question of whether the upfront cost pays back.
Calculation checklist
Divide a cents-per-kWh rate by 100 before multiplying. For example, 18¢/kWh becomes $0.18/kWh. Multiplying kWh by 18 would make the answer 100 times too large.
Annual kWh produces annual cost. Daily kWh produces daily cost. When annualizing a shorter period, show the conversion so the assumed usage pattern remains visible.
When comparing two products, use annual kWh figures for similar capacity and intended use. A lower-use model that does a different job is not a clean efficiency comparison.
A monthly account charge generally does not disappear when one appliance uses less electricity. Use the rate associated with energy consumption rather than automatically dividing every bill charge by kWh.
Appliance cost FAQ
A kilowatt is a rate of power use. A kilowatt-hour is energy used over time. A 1-kilowatt load running for two hours uses 2 kWh, which is the quantity multiplied by a per-kWh electricity rate.
Either can be valid if it is labeled. This guide uses 365 ÷ 12, about 30.42 days, when converting a steady daily estimate into an average month. For a specific billing period, use its actual number of days.
Not by multiplying rated watts by 24 hours a day. A refrigerator cycles, so its active runtime varies. Annual kWh from a comparable label or a representative measured-kWh period avoids assuming continuous full-power operation. Follow the appliance electricity measurement protocol before annualizing a household reading.
Official source
All dollar examples on this page are illustrative arithmetic at $0.18/kWh, not a claim about a particular appliance or household.
Build better inputs
Learn how to read the annual kWh on an EnergyGuide label, then find a defensible per-kWh rate on your electric bill. Those two inputs turn a generic estimate into a calculation based on your comparison and rate.