Electricity Cost Calculator

Estimate energy-use cost from watts and runtime, or enter total kilowatt-hours.

Consumption input mode

EIA residential reference: June 2026. Not an individual utility tariff.

Appliance power examples

Example assumptions only. Actual draw, cycling and runtime depend on the model and settings.

Watts, kilowatt-hours and operating days

EIA distinguishes power from energy: watts describe power; kilowatt-hours describe energy used over time. A 1,200-watt device running for one hour consumes 1.2 kWh. The expression is watts x hours / 1,000, not watts per hour.

Period energy
watts x hours per active day x active days / 1,000
Period cost
period kWh x price per kWh
365-day projection
period cost / period days x 365

For example, a 1,000-watt device used for one hour on one day in a 30-day period costs $0.15 at $0.15/kWh. Repeating that pattern gives about $1.83 over 365 days. Assuming use every day instead would cost $54.75, a different scenario.

Cost lookups at your selected rate

Rate: 0.1834 USD/kWh. Costs rounded to cents; other charges are not separately calculated.

EnergyCost
1.8 kWh$0.33
7 kWh$1.28
49 kWh$8.99
50 kWh$9.17
95 kWh$17.42
130 kWh$23.84
150 kWh$27.51
240 kWh$44.02
250 kWh$45.85
336 kWh$61.62
350 kWh$64.19
400 kWh$73.36
420 kWh$77.03
700 kWh$128.38
1,500 kWh$275.10
2,100 kWh$385.14
4,000 kWh$733.60
4,500 kWh$825.30
Power1 hour8 hours8h/day x 30 days
15 W$0.00$0.02$0.66
50 W$0.01$0.07$2.20
250 W$0.05$0.37$11.00
700 W$0.13$1.03$30.81
800 W$0.15$1.17$35.21
1200 W$0.22$1.76$52.82
1500 W$0.28$2.20$66.02
1600 W$0.29$2.35$70.43
2000 W$0.37$2.93$88.03
3000 W$0.55$4.40$132.05
4500 W$0.83$6.60$198.07
7700 W$1.41$11.30$338.92

EIA residential reference prices

U.S. average: 18.34 cents/kWh for June 2026. Source data collected 2026-09-13. These are residential sales averages, not a guaranteed tariff or forecast.

StateCents/kWhObservation month
Hawaii52.72June 2026
Maine29.59June 2026
Connecticut24.32June 2026
California34.74June 2026
New York29.49June 2026
Pennsylvania21.73June 2026
Michigan22.99June 2026
Florida15.10June 2026
Texas15.94June 2026
Missouri16.22June 2026
Nebraska13.25June 2026
North Dakota14.12June 2026
EIA Electric Power Monthly, Table 5.6.A

When a simple usage estimate differs from your bill

Fixed customer charges, demand charges, usage tiers, bill credits and time-of-use pricing can change the total. A state average cannot reproduce these rules. In a hypothetical time-of-use comparison, 2 kWh costs $0.60 at $0.30/kWh or $0.20 at $0.10/kWh; the applicable hours and prices depend on the utility.

Appliances that cycle need an appropriate runtime or measured average power. The FTC explains EnergyGuide labels, whose annual kWh figures help compare appliances under stated test assumptions. A label's estimated cost is not your personal bill.

Related calculations: EV charging, heat pumps, solar sizing and home energy audit. Savings depend on your actual usage and project assumptions, not a universal percentage.

Reviewed September 7, 2026. Estimates depend on the rate plan, usage pattern and operating conditions.

Frequently Asked Questions

What is the formula for electricity cost?

Energy in kWh equals watts x operating hours / 1,000. Multiply kWh by the price per kWh for an energy-use cost estimate. For repeated use, include the number of active days in the period.

How much does 150 kWh cost?

At $0.15 per kWh, 150 kWh costs $22.50. At $0.30 per kWh, it costs $45. Your utility bill may include additional charges or use a tiered or time-of-use tariff.

Why does annual cost depend on active days?

The 365-day projection repeats your entered pattern: period kWh / period days x 365 x rate. A device used once in 30 days is not assumed to run every day of the year. Seasonality, changes in prices and non-repeating usage are not predicted.

Why does a zero rate give zero cost?

A zero per-kWh rate gives zero usage cost. Fixed fees, demand charges and other bill items can still apply. This calculator does not separately model those charges.

Are the state reference rates my utility tariff?

No. EIA residential prices are state-level averages, not an individual utility offer. The observation month is shown separately from the collection date. Your rate plan can vary by season, usage tier, time of day and customer class.

Can I use nameplate watts for a refrigerator?

Appliances can cycle or vary their power draw. Multiplying a running wattage by 24 hours may overstate energy use. Annual kWh from an EnergyGuide label, a measured average power draw, or an appropriate active runtime may be a better basis. Avoid counting the same cycling adjustment twice.

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