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Electricity Bill Calculator
Enter your monthly usage and pick your state. Rates come from EIA data for August 2026.
How the calculation works
The arithmetic behind a residential electricity bill is simple:
- Usage × rate = kWh × cents per kWh ÷ 100
- Plus the fixed charge — but only if the rate you used is the per-kWh charge from your own bill
- Plus sales tax, where it applies, as a percentage of the subtotal
The state rates in the picker are EIA averages: total utility revenue divided by total sales. Delivery, riders and the fixed monthly charge are already spread across every kWh inside them, so with a state rate the first line is already close to the whole bill. Adding a fixed charge on top would count it twice.
The fixed charge still matters for one reason: it does not shrink when you cut usage. That is why a household that halves its consumption rarely sees its bill halve, and why a household using well below the state average pays a higher effective rate than the average shown.
Some utilities also use tiered rates, charging more per kWh above a monthly threshold, or time-of-use rates that vary by hour. The state average used here smooths both out. For an exact figure, take the rate directly from your own bill.
Common questions
Where do I find my kWh usage?
On your bill, usually labelled "kWh used" or "consumption" for the billing period. If you want an annual view, add up twelve months rather than multiplying one month by twelve — heating and cooling make usage very seasonal.
Why is the estimate different from my actual bill?
Three usual reasons: your utility's rate differs from the state average, your rate plan is tiered or time-of-use, or your usage is far from the state average, so the fixed charge is a bigger or smaller share of your bill than it is of the average. Override the rate field with the figure from your bill to remove the first.
What uses the most electricity in a home?
Air conditioning, then space heating and water heating — 43% of home electricity between them in EIA's 2020 figures — followed by lighting and refrigerators. Electronics are a much smaller share than most people expect. What uses the most electricity has the detail, and the appliance calculator breaks down individual devices.