LED Savings Calculator
Energy, money, and CO₂ saved by switching your bulbs to LED
Estimate only: CO₂ savings use the US grid-average emission factor (0.386 kg CO₂/kWh); your local grid's mix may differ. Dollar savings are based on the electricity rate you enter.
Related calculators
All energy- Heat Pump Savings CalculatorHeating savings vs electric resistance, gas, oil, or propane
- HVAC SEER Savings CalculatorCooling energy and cost saved by upgrading to a higher SEER
- Insulation Savings CalculatorAnnual heating cost saved by upgrading a surface's R-value
- Solar Panel CalculatorSystem size, cost after incentives, savings, and payback from your bill
- Carbon Footprint CalculatorAnnual household CO2 from energy and travel, broken down by source
- EV Savings CalculatorCompare electric vs gas fuel cost per year, per mile, and lifetime
Quick summary
Enter how many bulbs you're switching, their old and new wattage, hours used per day, and your electricity rate to see annual and 10-year savings plus CO₂ avoided. Swapping 20 sixty-watt incandescents (used 5 hours a day) for 9-watt LEDs saves roughly $150 a year and over 700 kg of CO₂. LEDs use about 80–85% less energy and last far longer, so you also save on replacement bulbs — a bonus not counted here.
Reviewed by Simple Calculators TeamLast reviewed
How to use this calculator
- Enter the inputs requested by the calculator.
- Choose the units or options that match your situation and review the assumptions.
- Run or update the calculation to see the result.
- Review the result, breakdown, and formulas shown on the page.
- Check the inputs, units, dates, and limitations before saving or sharing the result.
Frequently asked questions
How much does an LED bulb save vs incandescent?
An LED uses roughly 80–85% less electricity for the same brightness — a 9W LED replaces a 60W incandescent. Run 5 hours a day at $0.16/kWh, each bulb saves about $15 a year in electricity, plus years of replacement bulbs since LEDs last 15,000–25,000 hours.
How do I calculate the cost of running a light bulb?
Multiply watts ÷ 1000 × hours used × electricity rate. A 60W bulb on for 5 hours a day is 0.06 kW × 5 × 365 = 109.5 kWh a year, about $17.50 at $0.16/kWh. An equivalent LED costs a fraction of that. This calculator totals it across all your bulbs.
Are LEDs worth switching if my incandescents still work?
Usually yes — the energy savings often pay for the LED within months, especially for bulbs used many hours a day. Prioritize your most-used fixtures first; rarely-used closet bulbs matter less. The upfront LED cost is small next to years of reduced electricity bills.
Do LEDs really last longer?
Yes — quality LEDs are rated for 15,000–25,000+ hours versus about 1,000 for incandescents and 2,000 for halogens. That's 15–25× fewer replacements, cutting both cost and hassle, on top of the energy savings this calculator shows.
Key terms
- Watt
- A measure of power draw; lower watts for the same light means efficiency.
- Lumen
- The measure of brightness — compare bulbs by lumens, not watts.
- kWh
- Kilowatt-hour, the unit of energy your utility bills; watts × hours ÷ 1000.
Methodology, sources & limitations
This page shows the formula, assumptions, and limitations used for this estimate. Rates, thresholds, and other time-sensitive inputs can change, so verify them against the relevant official source before relying on a result.
For our review approach and the primary sources we consult, see the methodology and source policy. If you spot an outdated figure or formula, please contact us with a correction.