Bulb Electricity Cost & Runtime Matrix Calculator
Find out exactly how much any light bulb costs to operate per hour, per night, per month, and per year across single bulbs and whole-home arrays.
Quick Bulb Wattage Presets
Lighting & Runtime Settings
9.0 Watts
0.5W (LED)9W60W150W
6 Hours / Day
1 hr6 hrs12 hrs24 hrs (24/7)
$
Runtime Cost & Consumption Matrix
1 Bulb(s) × 9.0W = 9.0 Total Watts Connected
At Rate:$0.17 / kWh
| Operating Horizon | Energy Consumed | Estimated Cost |
|---|---|---|
| 1 Hour of Operation | 0.009 kWh | < $0.01 |
| 8-Hour Overnight Run | 0.072 kWh | $0.01 |
| 1 Day (24-Hour Continuous) | 0.216 kWh | $0.04 |
1 Month (30 Days at your daily hours) (30 days × 6 hrs/day) | 1.62 kWh | $0.28 |
1 Year (365 Days at your daily hours) (365 days × 6 hrs/day) | 19.7 kWh | $3.35 |
| 5 Years (Cumulative running cost) | 98.5 kWh | $16.75 |
The True Cost of Leaving Lights On
Leaving a single 9W LED bulb on 24 hours a day all year long costs less than $13.50 at average US rates ($0.17/kWh). By contrast, leaving an old 60W incandescent bulb on continuously burns approximately $89.35 per year in electricity alone — nearly 7× higher!