Question 1

How much does 1 kWh of electricity cost?

Accepted Answer

One kWh costs whatever your rate is: the US residential average is about 16.5¢, and across states it runs from roughly 11.5¢ in North Dakota to 42.9¢ in Hawaii. Your bill states the rate directly, usually as a price per kWh. A "unit" of electricity on a bill means one kWh, so 300 units and 300 kWh are the same thing. Switch the calculator to "A kWh amount" and enter any figure to price it at your rate.

Question 2

How much does it cost to run 1,500 watts for an hour?

Accepted Answer

A 1,500-watt device uses 1.5 kWh every hour, so at the US average rate of about 16.5¢/kWh it costs roughly $0.25 an hour, about $1.98 for an 8-hour day and $60.15 a month at that pace. That is the typical space-heater figure. The wattage table on this page covers the other common draws.

Question 3

How much does 500 kWh of electricity cost?

Accepted Answer

At the US average of 16.5¢/kWh, 500 kWh costs about $82.40. The same 500 kWh is about $57.55 in North Dakota and $214.30 in Hawaii: identical energy, very different bill. The kWh table on this page lists the common amounts, and the calculator prices any figure you type in.

Question 4

How much does 300 kWh per year cost?

Accepted Answer

At the US average of 16.5¢/kWh, 300 kWh a year costs about $49.44 a year, or $4.12 a month. "kWh per year" is the figure on an appliance's yellow EnergyGuide label; the dollar amount printed next to it uses one national average rate, so price the kWh at your own rate instead. The same 300 kWh is $34.53 a year in North Dakota and $128.58 in Hawaii.

Question 5

How do I calculate the cost to run an appliance?

Accepted Answer

Multiply the appliance's power in kilowatts (watts ÷ 1,000) by the hours it runs, then by your electricity rate. A 1,500-watt space heater for 8 hours a day at 16.5¢/kWh works out to about $1.98 a day, or roughly $60.15 a month. This calculator does the math and shows daily, monthly, and yearly cost at once.

Question 6

Where do I find an appliance's wattage?

Accepted Answer

Check the nameplate or label (often on the back or bottom), the manual, or the manufacturer's website. If it lists amps instead, multiply amps × volts (120 for most household outlets) to get watts. You can also pick a typical appliance from the list to start, then fine-tune the wattage.

Question 7

What electricity rate should I use?

Accepted Answer

Use the rate from your utility bill in dollars per kWh: it's the most accurate. If you don't have it handy, pick your state to fill in the average residential rate, then adjust. State averages range from 11.5¢ to 42.9¢ per kWh, and they exclude the fixed monthly service charge your utility adds on top of usage.

Question 8

Does this include standby or 'vampire' power?

Accepted Answer

Only if you account for it. Many devices draw a few watts even when off or idle. To include standby use, add the hours it sits plugged in at its standby wattage as a separate calculation, or raise the daily hours to reflect continuous low-level draw.

Energy used	US average16.48¢/kWh	North Dakota11.51¢/kWh	Hawaii42.86¢/kWh
0.5 kWh	$0.08	$0.06	$0.21
1 kWh	$0.16	$0.12	$0.43
2 kWh	$0.33	$0.23	$0.86
5 kWh	$0.82	$0.58	$2.14
10 kWh	$1.65	$1.15	$4.29
25 kWh	$4.12	$2.88	$10.72
50 kWh	$8.24	$5.76	$21.43
100 kWh	$16.48	$11.51	$42.86
150 kWh	$24.72	$17.27	$64.29
200 kWh	$32.96	$23.02	$85.72
250 kWh	$41.20	$28.78	$107
300 kWh	$49.44	$34.53	$129
400 kWh	$65.92	$46.04	$171
500 kWh	$82.40	$57.55	$214
750 kWh	$124	$86.32	$321
1,000 kWh	$165	$115	$429
1,500 kWh	$247	$173	$643
2,000 kWh	$330	$230	$857
2,500 kWh	$412	$288	$1,072

Label says	Per yearUS average	Per monthUS average	Per yearNorth Dakota	Per yearHawaii
50 kWh/yr	$8.24	$0.69	$5.76	$21.43
100 kWh/yr	$16.48	$1.37	$11.51	$42.86
150 kWh/yr	$24.72	$2.06	$17.27	$64.29
200 kWh/yr	$32.96	$2.75	$23.02	$85.72
250 kWh/yr	$41.20	$3.43	$28.78	$107
300 kWh/yr	$49.44	$4.12	$34.53	$129
350 kWh/yr	$57.68	$4.81	$40.29	$150
400 kWh/yr	$65.92	$5.49	$46.04	$171
500 kWh/yr	$82.40	$6.87	$57.55	$214
600 kWh/yr	$98.88	$8.24	$69.06	$257
700 kWh/yr	$115	$9.61	$80.57	$300
800 kWh/yr	$132	$10.99	$92.08	$343
1,000 kWh/yr	$165	$13.73	$115	$429

Power draw	Per hour	Per dayrunning 24 h	Per monthrunning 24/7
50 W	$0.0082	$0.20	$6.02
100 W	$0.0165	$0.40	$12.03
200 W	$0.0330	$0.79	$24.06
300 W	$0.0494	$1.19	$36.09
400 W	$0.0659	$1.58	$48.12
500 W	$0.0824	$1.98	$60.15
750 W	$0.1236	$2.97	$90.23
1,000 W	$0.1648	$3.96	$120
1,200 W	$0.1978	$4.75	$144
1,500 W	$0.2472	$5.93	$180
2,000 W	$0.3296	$7.91	$241
3,000 W	$0.4944	$11.87	$361
5,000 W	$0.8240	$19.78	$602

Electricity Cost Calculator

How much does a kWh of electricity cost?

What does an appliance’s kWh per year cost?

How much does it cost to run 1,000 watts for an hour?

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