Lighting Calculator

Calculate required lumens, fixtures, and wattage for optimal room lighting based on room dimensions and usage type.

Results

Total Lumens Needed
Fixtures Needed
Room Area:
Total Wattage:
Annual Cost (8hr/day):

About This Calculator

The Lighting Calculator helps determine optimal lighting levels for any room. It calculates total lumens needed based on room size and purpose, then recommends the number of fixtures required. Perfect for architects, interior designers, and homeowners planning lighting layouts.

How to Use

  1. Enter your room dimensions (length × width)
  2. Select the room type to determine required light levels
  3. Enter your bulb specifications (lumens and wattage)
  4. Click Calculate to see fixtures needed and energy costs

📚 Understanding Lighting Levels

Lumens measure the total amount of visible light emitted by a source. Higher lumens = brighter light. Different activities require different lighting levels for comfort and functionality.

Foot-candles (fc) measure light intensity at a surface. 1 foot-candle = 1 lumen per square foot. Professional lighting designers use foot-candles, but lumens per sq ft is easier for homeowners.

Layered lighting combines ambient (general), task (focused), and accent (decorative) lighting for optimal results.

🧮 Lighting Formulas

Total Lumens:
Lumens = Room Area (sq ft) × Lumens per sq ft
Number of Fixtures:
Fixtures = Total Lumens ÷ Lumens per Bulb

📊 Recommended Lumens by Room

Room TypeLumens/sq ftPurpose
Bedroom10-20Relaxation
Living Room20-30General activities
Kitchen50-70Food prep
Office60-80Computer/reading
Workshop80-100Detail work

💡 LED vs Traditional Bulbs

LumensLED (W)CFL (W)Incandescent (W)
4504-58-1240
8008-1213-1860
11009-1318-2275
160016-2023-30100

❓ FAQ

How do I choose the right color temperature?

Warm white (2700-3000K) for bedrooms/living rooms. Neutral white (3500-4000K) for kitchens/bathrooms. Cool white (5000-6500K) for offices/garages.

Should I use fewer bright bulbs or more dim ones?

More fixtures with lower output provides more even lighting and reduces shadows. Use multiple sources positioned around the room rather than one central fixture for best results.

? Frequently Asked Questions

How accurate is this

This calculator uses standard formulas and provides accurate results for typical use cases. For professional or critical applications, always verify results with certified professionals or official sources.

Is this calculator free to use?

Yes, this Lighting Calculator • Architecture • Calculator is completely free to use with no registration required. You can use it as many times as needed without any limitations.

Can I use this on mobile devices?

Absolutely! This calculator is fully responsive and works perfectly on smartphones, tablets, and desktop computers.

How do I interpret the results?

The results are displayed clearly with appropriate units. Refer to the "About This Calculator" section for detailed information.