Electricity Cost Calculator
What an appliance costs to run, per day, per month and per year, at your own tariff.
Runs entirely in your browser. Nothing is uploaded, logged or stored.
Cost per year
182.62
- Cost per month
- 15.22
- Cost per day it runs
- 0.50
- Kilowatt-hours per year
- 730.5
- Kilowatt-hours per month
- 60.9
- Kilowatt-hours per day it runs
- 2.000
A watt is a rate and a kilowatt-hour is an amount, which is the whole of the arithmetic: something drawing 2000 watts for an hour has used two kilowatt-hours, and what that costs is whatever your tariff says.
How it works
Watts times hours, divided by a thousand, times your price. The price is yours and never ours: a tariff differs by country, by supplier, by contract and by the hour of the day, so an average printed here would be wrong for nearly everybody reading it.
A year is taken as 365.25 days, so a week is 52.18 of them rather than 52. It sounds like pedantry, and for something used every day it is a day and a quarter of running over a year.
The power on the rating plate is what the appliance draws while it is actually working, which for anything that cycles — a fridge, a freezer, a heater with a thermostat — is not what it draws over an hour. For those, count the hours it is really running rather than the hours it is plugged in.
Examples
| Case | Input | Result |
|---|---|---|
| A tumble dryer twice a week | 2500 W, 1.5 h, 2 days, 0.25 | 3.75 kWh a run — about 98 a year |
| Something left on standby | 5 W, 24 h, 7 days, 0.25 | 43.8 kWh a year — about 11 |
| A gaming machine every evening | 400 W, 4 h, 7 days, 0.25 | 584 kWh a year — about 146 |
Frequently asked questions
Why does it not know my electricity price?
Because there is no such thing as the price. It differs between countries, between suppliers, between contracts, and on many tariffs between the hours of the day. Printing an average would give nearly every reader a wrong answer that looked authoritative. Yours is on your bill.
What about standing charges?
Not included, deliberately. A standing charge is what you pay whether the appliance runs or not, so adding it would inflate the cost of the thing you are asking about. What is shown is what running it adds.
My fridge says 150 W. Does it cost that all day?
No — the plate gives the draw while the compressor is running, and it runs perhaps a third of the time. For anything that cycles, put in the hours it actually works, or better, read the annual consumption from the energy label and divide it.
Which currency does the answer use?
Yours. The arithmetic multiplies, so whatever the price arrived in is what the answer is in. Naming a currency would be picking one.
Does it work for a gas appliance?
Yes, wherever gas is billed by the kilowatt-hour. Give the heat input on the appliance's plate — a 24 kW boiler is 24,000 W — the hours it burns, and your gas price per kilowatt-hour. To start from your meter readings instead, use the gas cost calculator.
Good to know
- Nothing here is sourced and nothing goes stale, because the only figure that could has been left to you.