Electricity Cost Calculator
Want to know what it really costs to run the dryer, leave the gaming PC on overnight, or run the air conditioner all afternoon in Texas? Enter the appliance wattage, hours of use, and your rate in cents per kWh — easily found on your latest utility bill — to see the daily, monthly, and annual cost.
How is this calculated?
kWh used = (watts ÷ 1000) × hours. Cost = kWh × price per kWh. U.S. residential electricity rates vary widely by state and utility — from around 11¢/kWh in Idaho and Washington to 30¢+/kWh in California and Hawaii, with the national average around 16¢/kWh in 2026. Time-of-use plans charge different rates by hour, and some utilities apply tiered pricing where the rate climbs once monthly usage crosses a threshold. Standby loads are included if you set hours to 24.
Frequently Asked Questions
How do I find my current rate per kWh?
It's printed on every electricity bill, usually labeled 'rate per kWh' or shown as a unit charge. Many utilities also show it in their app or online account. Tiered and time-of-use plans show multiple rates depending on time of day or monthly usage tier — your effective average rate is total bill divided by total kWh.
Why does my bill have so many extra charges?
U.S. residential bills typically split into generation, transmission, distribution, and various riders (renewable energy, public benefits, taxes). The bottom-line all-in rate per kWh is what matters for cost comparisons. State Public Utility Commissions oversee these charges and approval is required to change them.
Which appliances are the biggest culprits?
Anything that heats or cools intensively: central air conditioning (3–5kW), electric water heaters (4–5kW), electric dryers (3–4kW), electric ovens, and space heaters. Always-on devices add up too — a desktop PC running 24/7 at 100W costs around $140 a year at 16¢/kWh.
Are time-of-use plans worth switching to?
If you can shift heavy loads (EV charging, dryer, dishwasher) to off-peak windows, yes. California, Texas, and parts of the Northeast offer aggressive TOU plans that reward overnight use. If your usage is concentrated in peak hours (4pm–9pm summer), TOU can actually cost more than a flat rate — check before switching.
Last updated: May 2026 · Rates sourced from IRS