Enter your bulb count, wattage, and state. See annual savings, 10-year total cost, CO2 reduction, and how fast the LEDs pay back.
| Metric | Incandescent | LED | Savings |
|---|---|---|---|
| Run the calculator to see breakdown. | |||
Most homes still have incandescent bulbs in at least a few sockets. Maybe the bathroom vanity. The garage. The closet. They work fine and replacing them feels like a project. The problem is the math running in the background.
A standard 60-watt incandescent burns 60 watts of power. A 9-watt LED produces roughly the same 800 lumens. The LED is using 85 percent less electricity for the same light. Run 20 of those incandescent bulbs 3 hours a day at the national average rate and you are spending about $200 a year in electricity that an LED would not. That is before you count the replacement bulbs.
Incandescent bulbs last about 1,000 hours. An LED is rated for 15,000 to 25,000 hours. At 3 hours a day, one LED may cover more than 22 years of use. You would replace 15 to 25 incandescent bulbs in that same window. At $1 each, that adds up on top of the electricity cost.
The savings number swings dramatically by state. A California homeowner replacing 20 bulbs at $0.29 per kWh may save over $320 a year on electricity alone. A Texas homeowner at $0.13 per kWh saves closer to $145. Same bulbs, same usage, half the savings. This is why the state rate lookup matters. The national average is useful as a starting point. Your actual rate is the number that counts.
High-rate states (California, Connecticut, Massachusetts, New York, Hawaii) tend to have the fastest LED payback periods. Low-rate states (North Dakota, Idaho, Louisiana, Wyoming) have longer payback periods but still positive returns over any multi-year window.
The same 55.845 kWh saved per bulb (see the arithmetic below) multiplied by each state's rate produces the numbers above: at California's $0.29 a kWh that is $16.20 saved per bulb per year, $323.90 across 20 bulbs. At Texas's $0.13 a kWh that is $7.26 saved per bulb per year, $145.20 across 20 bulbs. Hawaii, the highest-rate state in the country at roughly $0.42 a kWh, would push the same 20-bulb swap to about $469 a year, while North Dakota's roughly $0.09 a kWh would put it closer to $101. The bulbs, the wattage, and the hours are identical in every case; only the local rate changes, and it changes the dollar answer by more than 4 to 1 between the cheapest and most expensive states.
LED bulbs used to cost $15 to $25 each. At that price, payback was measured in years. In 2026, a standard A19 LED replacement runs $1 to $2 in multi-packs. At $5 a bulb and 20 bulbs, you are spending $100 upfront. If those bulbs save $200 a year in electricity, payback is about 6 months. Most home improvement investments take years to pay back. LED bulbs typically pay back inside one year, and many households see payback in months.
The payback calculator above accounts for your specific electricity rate, usage hours, and bulb cost. If you are in a high-rate state or leave lights on longer, payback is faster.
Run the calculator's default inputs, 20 bulbs, a 60-watt incandescent swapped for a 9-watt LED, 3 hours a day, $0.18 a kWh, $1 incandescent bulbs, $5 LED bulbs, and here is exactly where the headline numbers come from. Each bulb runs 3 x 365 = 1,095 hours a year. The incandescent uses (60 x 1,095) / 1,000 = 65.7 kWh a year; the LED uses (9 x 1,095) / 1,000 = 9.855 kWh a year, a difference of 55.845 kWh per bulb. At $0.18 a kWh that is $10.05 saved per bulb per year, or $201.04 across 20 bulbs, matching the "$200 a year" figure above almost exactly.
Payback: 20 LED bulbs at $5 each is $100 upfront. $201.04 in annual savings works out to $16.75 a month, so $100 / $16.75 = 5.97 months to break even, just under 6 months, which is where the "about 6 months" payback claim comes from. Extend the same math to 10 years: $201.04 x 10 = $2,010.40 in electricity savings, plus bulb-replacement savings from not buying roughly 11 incandescent bulbs per socket over that decade (1,095 hours a year x 10 years = 10,950 hours, divided by a 1,000-hour incandescent lifespan) at $1 each versus the LEDs' single $5 purchase lasting the full period, for a 10-year total benefit of $2,129.42.
The FTC Lighting Facts label on every bulb package shows an "estimated annual energy cost" using $0.11 per kWh and 3 hours of use per day. That rate is a regulatory standard that has not kept pace with actual electricity prices. The EIA national average in early 2026 is about 18 to 19 cents per kWh. In California, rates are pushing 30 cents. If you rely on the label estimate, you are underestimating your actual savings by 50 to 100 percent depending on your state.
The calculator above uses your actual rate (or the EIA state average as a default). Results will typically be higher than the label estimate.
The EPA eGRID national average emissions factor for US electricity is about 0.85 pounds of CO2 per kWh. Saving 1,100 kWh per year (20 bulbs, 3 hrs/day) avoids about 935 pounds of CO2. That is roughly equivalent to removing a car from the road for about 1,200 miles. For a whole-house retrofit at 45 bulbs, the annual CO2 avoided is closer to 1,800 pounds. The environmental impact is real and measurable.
Every example on this page assumes 3 hours a day of use, a reasonable average for a mixed household of ambient and task lighting. A porch light or a security fixture that runs 10 to 12 hours a day sees roughly 3 to 4 times the electricity savings of the 3-hour example, since the kWh difference between an incandescent and an LED scales directly with hours run. A closet light that gets flipped on for 10 minutes a day sees a small fraction of it, and the payback period stretches out correspondingly, since the $5 LED bulb cost is fixed regardless of how little the bulb runs. Before assuming the national default numbers apply to a specific fixture, run that fixture's actual daily hours through the calculator above rather than the 3-hour household average.
Switching 20 incandescent 60-watt bulbs to 9-watt LEDs at the national average electricity rate of about 18 cents per kWh may save approximately $200 per year. Your actual savings depend on your electricity rate, how many hours per day the bulbs are in use, and how many bulbs you replace.
LED bulbs are designed to last approximately 15,000 to 25,000 hours, compared to about 1,000 hours for standard incandescent bulbs. At 3 hours of use per day, one LED bulb may last over 13 years before reaching 70 percent of original brightness (the L70 standard used by ENERGY STAR). Over that same period you might replace 15 to 25 incandescent bulbs.
A 9-watt LED bulb generally produces about the same light output (roughly 800 lumens) as a traditional 60-watt incandescent bulb, using about 85 percent less electricity. ENERGY STAR certified LED lamps are tested to produce 70 to 80+ lumens per watt, compared to about 15 lumens per watt for incandescent. For 40-watt replacement, look for a 6-watt LED. For 100-watt replacement, look for a 17-watt LED.
Each bulb's annual hours (3 hours a day x 365 days = 1,095 hours) times its wattage gives kWh used per year: 65.7 kWh for a 60-watt incandescent, 9.855 kWh for a 9-watt LED. The 55.845 kWh difference times $0.18 a kWh is $10.05 saved per bulb per year. Across 20 bulbs that is $201.04, which is where the "approximately $200 a year" figure comes from. Change your bulb count, hours, wattage, or rate above and the calculator reruns this exact arithmetic on your own numbers.
Yes, directly. The kWh saved per bulb scales with hours used, so a fixture running 10 hours a day saves roughly 3.3 times more electricity than the 3-hour household average, and pays back proportionally faster. A fixture running only 10 minutes a day saves very little electricity relative to the LED bulb's upfront cost, so payback stretches out to years instead of months. Enter your specific fixture's actual daily hours above rather than relying on the 3-hour default for a porch light, security light, or closet that gets used far more or less than average.
Disclaimer. This calculator is designed to provide general estimates of potential energy and cost savings from replacing incandescent bulbs with LED equivalents. Actual savings will vary based on your local electricity rate, usage patterns, specific bulb models, and other factors. Bulb prices are illustrative defaults and may differ from current retail prices. CO2 emission estimates are based on the EPA national average grid emissions factor and may not reflect your local utility's generation mix. This tool is for educational purposes and does not constitute a guarantee of savings.