kWh consumed and the daily, monthly and annual cost.
What it's for
Estimate what your appliances cost to run, and see which one takes the biggest share of the bill.
Before you start
Have your latest electric bill for the rate, and the wattage of each appliance from its label or nameplate. The page has no built-in rates, because they change every month and differ from one utility to another.
Enter your rate
In Rate per kWh, type the rate from your own bill, in digits only. If the bill does not print one, divide the total amount by the kWh used.
Set the number of days
In Days, type how many days to cost — the days in your billing period, for example.
List your appliances
Replace the example rows with your own: a name, its Watts, the Hours a day it is on, and How many of it you have. A row with no watts is skipped.
Add or remove rows
Press + Add appliance for each extra one, and ✕ at the end of a row to remove it.
Press Calculate
Press Calculate. The answer at the top already changes as you type; the button brings it back into view.
Reading the result
If it goes wrong
Watts times hours, divided by a thousand, gives kilowatt-hours. Multiply by your rate and you have the cost. The arithmetic is easy; what is hard is knowing which appliance to worry about.
So this takes several at once and shows each one's share of the total. Hours matter as much as watts — a 150 W refrigerator running all day beats eight 10 W bulbs running six hours — and that is not something an appliance label tells you.
On your own statement. Divide the total amount by the kilowatt-hours consumed, or read the effective rate your utility prints. This is the only figure that makes the answer yours rather than generic — rates differ by distribution utility, they change every month, and they vary with how much you consume.
Because any figure we bundled would be out of date within the month, and would differ from your bill by utility and by consumption bracket. A preset that looks authoritative and is quietly wrong is worse than asking you for one number. When published rates are transcribed and dated properly, presets can ship; until then the field stays yours.
No, and it will be lower. This is appliance consumption only. A real bill also carries generation and transmission charges, system loss, subsidies, universal charges and taxes. Use this to compare appliances against each other, not to predict the total.
Because hours matter as much as watts. A 150 W refrigerator running 24 hours uses more than eight 10 W bulbs running six. The wattage on the label tells you only half the story, which is why this asks for hours too.
The figure on the appliance label or nameplate. Note that many appliances do not draw their rated wattage continuously — an inverter aircon and a refrigerator both cycle — so a nameplate figure tends to overstate the real consumption.
gives kWh — then × your rate.
At any instant the fridge draws under twice what all eight bulbs draw together — 150 W against 80 W. Over a day it uses seven and a half times as much, because it never switches off. Nothing on the label tells you that.
Important
Appliance consumption only. A real bill also carries generation, transmission, system loss, subsidies and taxes, so it will come out higher than this. Nothing you type here is sent to our servers — the calculation runs entirely in your browser.
