Electricity Cost Calculator
Electricity Cost Calculator
Estimate the running cost of an electrical device from its power use, time, and energy rate.
Energy (kWh) = power (W) × hours/day × days ÷ 1,000Estimated cost = energy (kWh) × entered rate/kWhNot modeled: fixed charges, taxes, tiered rates, time-of-use rates, standby use, or duty cycles
What these items mean
The values and formats used by this tool have a practical meaning beyond the result. This short guide explains what they are, what they are used for, and where they came from.
Electrical quantities
Volts measure electrical potential difference, amps measure current, watts measure power, ohms measure resistance, and kilowatt-hours measure energy consumed over time. These values are used to size systems, compare appliances, estimate production, and understand a bill.
The concepts were developed by many scientists, including Alessandro Volta, André-Marie Ampère, James Watt, and Georg Ohm. Their names became units through later scientific and standards work; the equations describe relationships, not guaranteed real-world performance.
Authoritative resources
For energy context, check the U.S. Energy Information Administration electricity data and the U.S. Department of Energy’s energy-efficiency guidance.
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