Lumens to lux calculator
Lumens to lux calculator
What Lumens to lux calculator does
A lumens to lux calculator converts luminous flux in lumens to illuminance in lux, the light intensity falling on a surface. Users enter a lumen value, choose the area unit (square feet or square meters), and input either a spherical radius or surface area to receive the illuminance result in lux. The tool bridges the gap between total light output and practical light levels on a surface, supporting lighting design and engineering tasks. This RapidTables version stands out for offering both imperial and metric area units, with explicit formulas displayed for square feet and square meters calculations, allowing users to switch contexts without leaving the page. The interface presents input fields and result labels clearly, and the inclusion of a reciprocal lux to lumens link suggests a two-way conversion workflow within the same site ecosystem.
How to use the RapidTables Lumens to lux calculator
- 1
Enter the luminous flux value in lumens
- 2
Select the area unit type (square feet or square meters)
- 3
Input either the spherical radius in meters or the surface area in square meters
- 4
Press the Calculate button to view the illuminance result in lux
- 5
Use the Lux to lumens calculator link for reverse conversion
Best for
Lighting designers, architects, and engineers who need to convert total light output into surface illuminance levels using either imperial or metric measurements.
Limitations
- Requires user to know or estimate the surface area or radius for accurate results
- No automatic distance adjustment for non-spherical light distributions
- Conversion relies on standard formulas; real-world fixture placement may vary
Lumens to lux calculator FAQ
- How do I convert lumens to lux for a room?
- Enter the total lumens of your light source, choose square feet or square meters for the room area, and the calculator will divide the flux by the area to give you the illuminance in lux.
- Can I use radius instead of area?
- Yes, the tool offers a spherical radius option; entering a radius in meters calculates illuminance using the surface area of a sphere formula.
- Is the result affected by ceiling height?
- The calculator assumes uniform distribution over the specified area; for precise room planning, consider fixture spacing and mounting height separately.
- What is the formula used for square meters?
- Lux equals lumens divided by the surface area in square meters (lx = lm / m²).