What it costs to run any device, from its watts
A 100 W device left on 8 hours a day uses 292 kWh a year and costs $50.52 at the U.S. price, $118.52 in Hawaii and $34.49 in North Dakota. Type any watts and hours below.
Your device
Map: where a watt costs most
- 11.8 ¢ to 13.2 ¢
- 13.2 ¢ to 15.0 ¢
- 15.0 ¢ to 16.2 ¢
- 16.2 ¢ to 22.9 ¢
- 22.9 ¢ to 40.6 ¢
Darker = a kWh costs more.
The 51 states with CSV
| Hawaii | 40.59 | 40.59 ¢ | $118.52 | $148.15 | 60.9 ¢ |
|---|---|---|---|---|---|
| California | 32.54 | 32.54 ¢ | $95.02 | $118.77 | 48.8 ¢ |
| Massachusetts | 30.48 | 30.48 ¢ | $89.00 | $111.25 | 45.7 ¢ |
| Rhode Island | 29.46 | 29.46 ¢ | $86.02 | $107.53 | 44.2 ¢ |
| Connecticut | 29.38 | 29.38 ¢ | $85.79 | $107.24 | 44.1 ¢ |
| Maine | 27.78 | 27.78 ¢ | $81.12 | $101.40 | 41.7 ¢ |
| New York | 26.39 | 26.39 ¢ | $77.06 | $96.32 | 39.6 ¢ |
| Alaska | 26.09 | 26.09 ¢ | $76.18 | $95.23 | 39.1 ¢ |
| New Hampshire | 24.56 | 24.56 ¢ | $71.72 | $89.64 | 36.8 ¢ |
| Vermont | 22.92 | 22.92 ¢ | $66.93 | $83.66 | 34.4 ¢ |
| New Jersey | 22.63 | 22.63 ¢ | $66.08 | $82.60 | 33.9 ¢ |
| District of Columbia | 21.94 | 21.94 ¢ | $64.06 | $80.08 | 32.9 ¢ |
| Michigan | 20.01 | 20.01 ¢ | $58.43 | $73.04 | 30.0 ¢ |
| Maryland | 19.48 | 19.48 ¢ | $56.88 | $71.10 | 29.2 ¢ |
| Pennsylvania | 19.30 | 19.30 ¢ | $56.36 | $70.44 | 29.0 ¢ |
| Wisconsin | 18.16 | 18.16 ¢ | $53.03 | $66.28 | 27.2 ¢ |
| Illinois | 17.69 | 17.69 ¢ | $51.65 | $64.57 | 26.5 ¢ |
| Delaware | 17.13 | 17.13 ¢ | $50.02 | $62.52 | 25.7 ¢ |
| Ohio | 16.96 | 16.96 ¢ | $49.52 | $61.90 | 25.4 ¢ |
| Indiana | 16.23 | 16.23 ¢ | $47.39 | $59.24 | 24.3 ¢ |
| Alabama | 16.10 | 16.10 ¢ | $47.01 | $58.77 | 24.2 ¢ |
| Colorado | 15.85 | 15.85 ¢ | $46.28 | $57.85 | 23.8 ¢ |
| Minnesota | 15.82 | 15.82 ¢ | $46.19 | $57.74 | 23.7 ¢ |
| Texas | 15.47 | 15.47 ¢ | $45.17 | $56.47 | 23.2 ¢ |
| West Virginia | 15.41 | 15.41 ¢ | $45.00 | $56.25 | 23.1 ¢ |
| Oregon | 15.37 | 15.37 ¢ | $44.88 | $56.10 | 23.1 ¢ |
| Arizona | 15.32 | 15.32 ¢ | $44.73 | $55.92 | 23.0 ¢ |
| Virginia | 15.28 | 15.28 ¢ | $44.62 | $55.77 | 22.9 ¢ |
| Florida | 15.24 | 15.24 ¢ | $44.50 | $55.63 | 22.9 ¢ |
| New Mexico | 15.08 | 15.08 ¢ | $44.03 | $55.04 | 22.6 ¢ |
| South Carolina | 14.96 | 14.96 ¢ | $43.68 | $54.60 | 22.4 ¢ |
| Georgia | 14.73 | 14.73 ¢ | $43.01 | $53.76 | 22.1 ¢ |
| Kansas | 14.56 | 14.56 ¢ | $42.52 | $53.14 | 21.8 ¢ |
| Mississippi | 14.03 | 14.03 ¢ | $40.97 | $51.21 | 21.0 ¢ |
| North Carolina | 14.02 | 14.02 ¢ | $40.94 | $51.17 | 21.0 ¢ |
| Iowa | 13.72 | 13.72 ¢ | $40.06 | $50.08 | 20.6 ¢ |
| Missouri | 13.49 | 13.49 ¢ | $39.39 | $49.24 | 20.2 ¢ |
| South Dakota | 13.38 | 13.38 ¢ | $39.07 | $48.84 | 20.1 ¢ |
| Wyoming | 13.38 | 13.38 ¢ | $39.07 | $48.84 | 20.1 ¢ |
| Kentucky | 13.24 | 13.24 ¢ | $38.66 | $48.33 | 19.9 ¢ |
| Tennessee | 13.18 | 13.18 ¢ | $38.49 | $48.11 | 19.8 ¢ |
| Nevada | 13.15 | 13.15 ¢ | $38.40 | $48.00 | 19.7 ¢ |
| Oklahoma | 13.12 | 13.12 ¢ | $38.31 | $47.89 | 19.7 ¢ |
| Washington | 13.11 | 13.11 ¢ | $38.28 | $47.85 | 19.7 ¢ |
| Utah | 13.07 | 13.07 ¢ | $38.16 | $47.71 | 19.6 ¢ |
| Montana | 12.98 | 12.98 ¢ | $37.90 | $47.38 | 19.5 ¢ |
| Arkansas | 12.84 | 12.84 ¢ | $37.49 | $46.87 | 19.3 ¢ |
| Louisiana | 12.57 | 12.57 ¢ | $36.70 | $45.88 | 18.9 ¢ |
| Nebraska | 12.34 | 12.34 ¢ | $36.03 | $45.04 | 18.5 ¢ |
| Idaho | 11.82 | 11.82 ¢ | $34.51 | $43.14 | 17.7 ¢ |
| North Dakota | 11.81 | 11.81 ¢ | $34.49 | $43.11 | 17.7 ¢ |
Price × kWh. 100 W × 8 h × 365 = 292 kWh; 1,000 W × 1 h × 365 = 365 kWh.
CSVThe formula
DOE Energy Saver: (watts × hours a day) ÷ 1,000 = kWh a day; × days used = kWh a year; × price per kWh = cost. Their worked example: a 1,500 W kettle used 1 hour a day uses 547.5 kWh a year. Wattage is on the label or equals amps × volts (120 V for most plug-in devices, 240 V for large ones). A plug-in energy monitor ($25 to $50, DOE) reads real use for a 120 V device.
Sources and dates
| Source | Period | Retrieved | Licence | Used for |
|---|---|---|---|---|
| EIA electricity retail sales, annual and monthly (API v2) | annual 2010 to 2025, monthly to Jul 2026 | 1 Oct 2026 | U.S. government data, public domain; cite EIA | Home price 2025 |
| DOE Energy Saver: Estimating Appliance and Home Electronic Energy Use | formula and worked examples | 2 Oct 2026 | U.S. government publication, public domain | Formula |
All other site sources, with join keys: data sources.
More
Questions
How do I work out what a device costs to run?
Watts times hours a day divided by 1,000 gives kWh a day. Multiply by days and by your price per kWh.
Where do I find the wattage?
On the label or nameplate, or amps times volts. It is the maximum draw; many devices use less most of the time (DOE).
What does 1 kWh cost?
17.30 cents at the U.S. average home price of 2025; 11.81 in North Dakota and 40.59 in Hawaii.
How much does a 1,500 W heater cost an hour?
26.0 cents at the U.S. average price; 60.9 cents in Hawaii.
Do devices use power when off?
Many draw a few watt-hours as standby (DOE calls them phantom loads); a plug-in monitor or a power strip switch shows or removes it.
Is my price the state average?
Not exactly: your plan, fixed charges, tiers and time-of-use hours differ; the table uses EIA's 2025 average.
Why no space heater, microwave or router pages?
We include an appliance only when an open source (ENERGY STAR data, DOE) gives its power or yearly energy. The generic calculator here covers the rest if you enter the watts from the label.
What about a refrigerator?
Fridges cycle on and off, so use the yearly kWh on the EnergyGuide label rather than watts times 24 hours.
Space heaters
Heater watts are on the label. For the cost of a space heater by state, at 750 W, 1,000 W and 1,500 W, with a heat pump comparison, see what a space heater costs to run.