About Billowatt

Billowatt answers one deceptively simple question — "how much does this cost to run?" — correctly.

Most answers on the internet are wrong for a boring reason: they assume a single national electricity price, often one from years ago. Real U.S. residential rates currently span from about 12.4¢ to 46.6¢ per kilowatt-hour — a spread wide enough that the same space heater can cost $40 or $115 a month depending on where it's plugged in. An answer that ignores your state isn't an estimate; it's a coin flip.

So we built the version we wanted: 157 appliances with realistic wattage and usage data, priced with current, state-level rates refreshed monthly from U.S. Energy Information Administration data, with calculators on every page so you can swap in your own habits. No account, no app, no upsell — the site is free, supported by advertising.

What we care about

• The answer first. Every page leads with the number you came for, then shows the assumptions behind it.
• Current data. Rates carry their vintage (April 2026 right now) and update on a schedule, not "whenever."
• Honest magnitudes. We'll tell you when something costs pennies and isn't worth optimizing — unplugging your toaster is not a savings plan.

How every figure is computed, including sources and formulas, is documented on the methodology page. Corrections and suggestions are genuinely welcome via the contact page.