What will your Christmas lights cost?
Use your actual wattage, schedule and electricity rate.
The calculation
Watts ÷ 1,000 × hours per day × days × price per kWh.
For the example: 120 W ÷ 1,000 × 6 hours × 30 days = 21.6 kWh. At $0.20 per kWh, that is $4.32 in energy charges.
Find the right inputs
Use the stated power consumption for the equipment, or an appropriate measured figure, rather than guessing from bulb count. Add the watts for devices that run on the same schedule. If parts of the display run different hours, calculate them separately and add the results.
Use the applicable variable energy rate from your electricity bill. If the rate is written as 20 cents per kWh, enter 0.20. Fixed fees, tiered or time-dependent rates, taxes and other charges are outside this simple estimate.
What this number does not tell you
This is an energy-cost estimate, not an electrical capacity or safety assessment. It does not determine whether a circuit, extension cord, timer or installation can support the load.
Plan timers and power →A little plan for your kind of Christmas.
Save a favorite idea, note the space you have and start with the pieces you already love. Add the rest when you’re ready.