Know your bill.
Appliance Power Consumption Calculator
Enter an appliance's wattage and usage to see its energy in kWh and its running cost across a day, week, month, and year - using 27 presets and 15 currencies.
Private · Local · No account
- 27 appliance presets
- 15 currencies
- No account required
Measure any appliance
Live - local onlyYour results will appear here
Pick an appliance or enter watts, set usage hours and your electricity price, then press Calculate.
All calculations run locally in your browser. Your inputs are never sent to a server.
One formula, four timeframes, real numbers.
Pick the appliance
Choose a preset or enter the running watts printed on the device label.
Set the usage
How many units, hours per day, and days per week the device actually runs.
Apply your tariff
Enter your price per kWh and read the estimated cost per day, month, and year.
What this estimate assumes
This calculator estimates energy from the wattage you enter: kWh/day = watts × quantity × hours ÷ 1,000. The monthly figure uses a 365.25-day year divided by 12, and the weekly figure uses your days-per-week directly.
Appliances with thermostats or cycles - refrigerators, air conditioners, ovens, washing machines - draw less on average than their rated wattage, so treat the result as a planning estimate, not a meter reading.
Cost multiplies your kWh by your unit rate only. Standing charges, taxes, and time-of-use tariffs are not included. When in doubt, use the price per kWh printed on your latest bill.
The formula
kWh/day = watts × units × hours per day ÷ 1,000
Cost = kWh × price per kWh
Worked example: a 1,500 W space heater running 5 hours a day at $0.16/kWh uses 7.5 kWh/day - about 228 kWh and $36.53 per month, or $438 per year. Try it with the Load example button.
Watts vs kilowatt-hours
Watts measure the rate of use at an instant; kilowatt-hours measure the total energy used over time. A 100 W bulb on for 10 hours uses 1 kWh. Your meter counts kWh and your bill charges per kWh - the watts figure alone never appears on a bill, which is why this calculator converts before it prices anything.
Prefer the full method? The step-by-step guide explains the formula, how to read a rating label, and how to check the result against your bill: How to Calculate Appliance Power Consumption.
Guides worth reading
How to Calculate Appliance Power Consumption: A Step-by-Step Guide
The formula behind every estimate, how to read a rating label, and the step-by-step path from watts to your bill's unit rate.
Read articleHow Many Watts Does a Refrigerator Use? Typical Consumption Explained
Running vs start-up watts, typical daily kWh by fridge size, and the factors that quietly raise a fridge's running cost month to month.
Read article10 Practical Ways to Reduce Your Home Electricity Bill
The biggest savings come from heating, cooling, water heating and standby loads — not from unplugging phone chargers. Ten practical, low-effort changes.
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