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Electricity Cost Calculator

A quick way to estimate an appliance's running cost, or sanity-check your utility bill.

Electricity used (kWh)

Rate per kWh ($)

Cost

135

Check a recent bill for your actual per-kWh rate — it often varies by season or usage tier.

What you entered

Electricity used (kWh): 900Rate per kWh ($): 0.15

1
Apply the per-kWh rate
900 kWh × $0.15= $135

Result

Cost: 135

900 kWh at $0.15/kWh comes to $135.

Monthly running cost of common household appliances at $0.16 per kWh

Usage is power in watts multiplied by hours of use per day, divided by 1,000, over a 30-day month. The rate is $0.16 per kWh, close to the US residential average. Type the kWh per month figure and your own rate into the calculator to reprice any row.

Appliance	Power (W)	Hours per day	Usage (kWh per month)	Cost per month at $0.16/kWh
LED light bulb	10	5	1.5	$0.24
Laptop computer	60	8	14.4	$2.30
55-inch LED TV	100	5	15.0	$2.40
Desktop PC and monitor	250	6	45.0	$7.20
Clothes dryer	3,000	1	90.0	$14.40
Refrigerator (average draw)	150	24	108.0	$17.28
Window air conditioner	1,000	8	240.0	$38.40
Space heater	1,500	6	270.0	$43.20
Electric water heater	4,000	3	360.0	$57.60
Central air conditioner	3,500	6	630.0	$100.80

Illustrative figures, not a bill estimate. Wattages vary widely by model, and appliances with a thermostat (refrigerators, heaters, air conditioners) cycle on and off rather than drawing full power continuously, so the hours shown are effective full-power hours. US rates range from about $0.11 per kWh in Louisiana to over $0.40 in Hawaii, and many plans charge more during peak hours, so check the $/kWh line on your own bill.

Finding your actual rate

Your rate per kWh is on your electric bill, usually listed as '$/kWh' or similar — rates often vary by time of day (peak vs. off-peak) or season, so a single flat rate here is an approximation, not a perfectly precise bill.

Estimating appliance costs

To estimate what a specific appliance costs to run, multiply its wattage by hours used, divide by 1000 to get kWh, then use this calculator — a good way to spot which appliances are actually driving up your bill.

Frequently asked questions

My space heater is 1,500 watts and I run it 6 hours a day — what does that cost per month?

1,500 W × 6 hrs = 9,000 Wh = 9 kWh/day. At the US average of $0.16/kWh, that's $1.44/day or about $43/month. Space heaters are one of the most expensive appliances to run — often more than the rest of your electronics combined.

How is this different from the Water Bill Calculator?

This calculator estimates electricity costs from kWh usage and your per-kWh rate. The Water Bill Calculator estimates water costs from volume used, per-unit water rate, and a flat base fee. They use the same price × usage logic but for different utilities.

Where do I find my electricity rate?

Look on your electric bill for a line item showing $/kWh — the US average is about $0.16/kWh, but it ranges from $0.10 in states like Louisiana to $0.35+ in Hawaii and California. Some plans have time-of-use rates (cheaper at night, more expensive during peak hours).

Does leaving things plugged in use electricity even when they're off?

Yes — 'vampire' or standby power draws 5–10 watts per device. A TV, game console, and cable box on standby can cost $50–$100/year combined. Smart power strips that cut power completely when devices are off can eliminate this.