Lightbulb Cost vs LED
Compare the running cost of old bulbs against LEDs.
About Lightbulb Cost vs LED
Multiplying each bulb's wattage by annual use and the number of bulbs gives the yearly cost. LEDs use far fewer watts for the same light, so the difference is the savings. Lighting a full house with old bulbs quietly drives a large recurring charge that switching to LEDs mostly eliminates.
Formula
Lightbulb Cost vs LED
Cost = watts x hours x days x bulbs x rate / 1000
- watts
- Power draw per bulb
Worked example
With the default values below, Lightbulb Cost vs LED returns Old Bulbs Annual of $105.12. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Old bulb wattsminimum 0 watts
- 60 watts
- LED wattsminimum 0 watts
- 9 watts
- Number of bulbsminimum 1
- 8
- Use per dayminimum 0 hours
- 4 hours
- Electricity rateminimum 0 $/kWh
- 0.15 $/kWh
Results
- Old Bulbs Annual
- $105.12
- LED Annual
- $15.77
- Annual Savings
- $89.35
- Energy Saved/year
- 595.7 kWh
Step by step
- 1Values used
- 2Lightbulb Cost vs LED
- 3Old Bulbs Annual= 105.12
- 4LED Annual= 15.77
- 5Annual Savings= 89.35
- 6Energy Saved/year= 595.7 kWh
Assumptions and limits
- The result is derived only from the 5 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Lightbulb Cost vs LED calculated?
Cost = watts x hours x days x bulbs x rate / 1000 Multiplying each bulb's wattage by annual use and the number of bulbs gives the yearly cost. LEDs use far fewer watts for the same light, so the difference is the savings.
Why does Lightbulb Cost vs LED matter?
Lighting a full house with old bulbs quietly drives a large recurring charge that switching to LEDs mostly eliminates.
What values do I need to enter?
This calculator takes 5 inputs: Old bulb watts, LED watts, Number of bulbs, Use per day, Electricity rate. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.