Electricity guides

Understand the numbers behind your power bill.

These guides explain the concepts our calculators use: watts, kilowatt-hours, electricity rates, utility bills, home energy use, and EV charging.

How to read an electric billFind kWh, your rate, fixed charges, and the lines that actually move your total.Bill basics → What is a kilowatt-hour?Why watts measure power while kWh measure energy, with simple household examples.Learn kWh → Why electricity prices vary by stateFuel mix, infrastructure, regulation, weather, and local market structure all matter.Compare prices → How to estimate an appliance's electricity costA reusable method for turning watts, run time, and cents per kWh into dollars.Use the formula → What uses the most electricity in a home?Why heating, cooling, and water heating usually matter more than small electronics.Find the big loads → How EV charging costs workBattery energy, wall energy, charging losses, efficiency, and home electricity prices.Understand EV charging → Electricity rate vs. total billWhy cents per kWh can differ from the all-in cost of a utility statement.Separate rate from bill → How electric utility rates workGeneration, delivery, fixed charges, competitive supply, tiers, and time-of-use pricing.Understand rate design →

How we research

See how we source, calculate, and update information.

Our Editorial Standards page explains our use of EIA data, calculation checks, corrections, and the line between historical averages and current tariffs.

Editorial Standards →