💡 LED vs Incandescent Cost Calculator

Compare the running cost of an LED bulb against an incandescent bulb over your chosen usage period.

Both bulbs, priced by the kilowatt-hour

Each side is the same sum, run on its own wattage:

yearly cost = watts / 1000 x hours per day x 365 x rate per kWh
saving      = incandescent cost - LED cost

A 9 W LED against a 60 W incandescent at 5 hours a day uses 16.4 kWh a year instead of 109.5. At $0.15 a kWh that is $2.46 against $16.43, so the LED saves $13.96 a year and $139.61 over ten. Your own rate changes this more than the bulbs do: the 93 kWh saved is worth $37.23 a year where power costs 40 cents, and $10.24 where it costs 11. Take the figure from your bill.

Match the lumens, not the watts

Wattage measures consumption, not light. Buy by lumens: 800 lm replaces the old 60 W bulb and needs 8 to 10 W of LED, 1,100 lm replaces a 75 W, and 1,600 lm replaces a 100 W. Colour temperature is separate - 2700K matches the warm tone of the bulb you are replacing, 4000K and above looks clinical in a living room.

Only energy is counted here. An incandescent lasts about 1,000 hours and an LED 15,000 or more, so over the 18,250 hours in that ten-year figure you would buy roughly eighteen of one and one of the other. Bulb prices make the real gap wider than the tool shows.

Frequently asked questions

How much does one LED bulb save per year?

About $14 replacing a 60 W bulb used 5 hours a day at 15 cents a kWh. The saving scales with both: half the hours halves it, and a 40 cent rate lifts it to roughly $37.

What LED wattage replaces a 60 watt bulb?

Around 9 W, for the 800 lumens a 60 W incandescent produced. Anything from 8 to 10 W is the same brightness to the eye; the number that must match is the lumens on the box.

Is it worth replacing bulbs that still work?

For a light on several hours a day, yes - a $2.50 LED pays for itself in about two months of the $1.16 a month it saves. For a cupboard light used ten minutes a day the saving is 56 cents a year and the swap takes over four years to pay back, so use those bulbs up first.