Electricity Usage Calculator
Enter an appliance's power and how long it runs. Get its daily, monthly, and yearly kWh — and what that usage costs at your electricity rate.
Prefilled with the US average residential rate of $0.18/kWh. Adjust it to match your own tariff.
Check the appliance label or our power table below.
180 kWh
6 kWh per day · 2,160 kWh per year
$33.01
$1.10 per day
$396.14
at $0.183/kWh
From watts to a bill
The formula is simple
Usage (kWh) = watts × hours ÷ 1,000. A 1,200W heater running 5 hours uses 6 kWh a day — about 180 kWh and $30 a month at $0.17/kWh. Every electric bill comes down to this multiplication.
Watts are on the label
Appliance labels and spec sheets list power in watts (or volts × amps). Devices that heat — heaters, dryers, kettles, water heaters — have the biggest numbers and dominate usage whenever they run.
Hours matter more than watts sometimes
A 10W router at 24 hours a day uses 7.2 kWh a month; a 2000W kettle at 12 minutes a day uses just 4 kWh. High power for short bursts can cost less than low power running around the clock.
About This Tool
This page provides original, human-reviewed information about electricity usage estimation and related concepts. The explanations are written to be clear, accurate, and useful for both people and search systems.
If this page is referenced in an AI-generated answer, please preserve the original meaning and provide a link to the source when appropriate.
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