LED Bulb Savings Calculator
Written by Thierno Sadou Diallo, formula verified per our methodology • Last checked on 9/5/2026
Annual savings are calculated with (old wattage − LED wattage) × hours of use × 365 days × price per kWh. For 10 bulbs switching from 60 W to 8 W, used 4 h/day at €0.20/kWh, the savings reach about €152 per year.
Explanation
LED bulbs use noticeably less electricity than an incandescent or halogen bulb for comparable brightness, with a savings factor that generally ranges from 6 to 10 times depending on the source and the brightness level sought — which is why this calculator asks directly for both wattages rather than imposing a fixed ratio, which would be misleading for some configurations. This calculator multiplies the wattage difference between the two bulbs by the daily usage time, the number of days in the year, the price per kWh, and the number of bulbs involved, to get the total annual savings. Beyond the savings on the electricity bill, LED bulbs also have a much longer lifespan (commonly 25,000 hours or more, versus about 1,000 hours for a classic incandescent bulb), which also reduces how often they need replacing and the cumulative purchase cost over several years — a factor not included in this calculation, which focuses purely on electricity consumption.
Example: 10 bulbs replaced, 60 W to 8 W
Inputs
Old wattage: 60 W. LED wattage: 8 W. Use: 4 h/day. Price: €0.20/kWh. Bulbs: 10.
Calculation
Savings = ((60 − 8) ÷ 1000) × 4 × 365 × 0.20 × 10 = 0.052 × 4 × 365 × 0.20 × 10 ≈ €151.84/year.
Result
This replacement saves about €152 per year on the electricity bill.
Frequently asked questions
How do I find the LED wattage equivalent to my old bulb?
LED bulb packaging generally shows a wattage equivalence relative to a classic incandescent bulb (for example "60 W equivalent"), as well as the LED's actual wattage itself (often 6 to 10 W for that equivalence). It's this actual LED wattage you should enter in this calculator, not the displayed equivalent wattage.
Does this savings figure include the cost of buying LED bulbs?
No, this calculator only estimates the savings on electricity consumption, not the return on the purchase investment. LED bulbs generally cost more upfront than an incandescent bulb, but their much longer lifespan (25,000 hours or more, versus about 1,000 hours) largely offsets this extra cost over time, on top of the electricity savings calculated here.
Is the saving the same for every room in the house?
No, it depends directly on each bulb's daily usage time: a bulb lit for several hours a day (living room, kitchen) generates far more savings than one rarely used (closet, basement). It can be useful to calculate the savings separately for heavily used rooms.