LED Lighting Calculator

The LED Lighting Calculator tells you exactly how many light fixtures you need to properly illuminate any room, based on its size and how you use it. Enter your room length, width, and ceiling height, then select your room type, lighting intensity, wall color, and lumens per bulb to get the number of LED fixtures needed. Secondary outputs include total lumens required, lumens per square foot, and room area.

ft
ft
ft

Lighting Intensity *

Wall Color *

lumens

Check your LED bulb packaging for lumen output

Results

LED Fixtures Needed

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Total Lumens Required

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Lumens per Square Foot

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Room Area

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Frequently Asked Questions

How many lumens per square foot do I need?

The lumens per square foot needed depends on the room type and use. Bedrooms typically need 10-20 lumens/sq ft, living rooms 10-20, kitchens 30-40, and task areas up to 50 lumens/sq ft for detailed work.

How do I calculate the lighting for a room?

Calculate room area (length × width), determine required lumens per square foot based on room type, multiply area by lumens/sq ft for total lumens needed, then divide by your bulb's lumen output to find number of fixtures needed.

What is the difference between lumen and lux?

Lumens measure the total light output from a source, while lux measures how much light falls on a surface (lumens per square meter). Lumens indicate brightness of the bulb, lux indicates brightness on your work surface.

What is the best lighting for a bedroom?

Bedrooms work best with layered lighting: ambient lighting at 10-20 lumens/sq ft, task lighting for reading at 30-50 lumens/sq ft, and accent lighting for atmosphere. Use warm color temperatures (2700K-3000K) for relaxation.

How does ceiling height affect lighting calculations?

Higher ceilings require more lumens because light spreads over a larger area and loses intensity with distance. For ceilings over 9 feet, increase your lumen requirements by 10-20% for adequate illumination.

Do wall colors affect lighting requirements?

Yes, wall colors significantly impact lighting needs. Light-colored walls reflect more light and reduce fixture requirements, while dark walls absorb light and may require 10-15% more lumens for the same brightness level.

How many LED lights do I need for a 12x10 room?

For a 120 sq ft room, you typically need 1,200-6,000 total lumens depending on use (10-50 lumens/sq ft). With 800-lumen LED bulbs, this means 2-8 fixtures depending on the room's purpose and your brightness preference.

Can I use this calculator for outdoor lighting?

This calculator is designed for indoor spaces. Outdoor lighting has different requirements due to weather, safety needs, and larger areas. For outdoor spaces, consult specific outdoor lighting guidelines or professional lighting designers.