Elara Bennett15 lumens equals 15 lux when the light is spread evenly over an area of one square meter.
Lux measures illuminance, which is the amount of light falling on a surface area. Since 1 lux equals 1 lumen per square meter, converting lumens to lux depends on the surface area the light covers. Here, assuming the light is spread over 1 square meter, 15 lumens converts directly to 15 lux.
Conversion Tool
Result in lux:
Conversion Formula
The formula to convert lumens to lux is:
Lux = Lumens / Area (in square meters)
This works because lux measures how much luminous flux (lumens) illuminates a surface area. If you know total lumens emitted and the surface size, dividing lumens by area gives illuminance.
For example, if 15 lumens spread over 1 square meter:
- Lux = 15 lumens / 1 m²
- Lux = 15
If the same 15 lumens spread over 0.5 m²:
- Lux = 15 lumens / 0.5 m²
- Lux = 30
Smaller area means higher lux; bigger area lowers lux.
Conversion Example
- Convert 30 lumens over 2 m²:
- Divide 30 by 2
- Lux = 15
- Convert 45 lumens over 3 m²:
- 45 ÷ 3 = 15 lux
- Convert 60 lumens over 4 m²:
- 60 ÷ 4 = 15 lux
- Convert 75 lumens over 5 m²:
- 75 ÷ 5 = 15 lux
- Convert 90 lumens over 6 m²:
- 90 ÷ 6 = 15 lux
Conversion Chart
This chart shows lumens values from -10.0 to 40.0 and their equivalent lux, assuming illumination over 1 square meter. Negative lumens are physically impossible but included for mathematical completeness. Use this chart to quickly find lux without calculation if area is 1 m².
| Lumens | Lux (assuming 1 m² area) |
|---|---|
| -10.0 | -10.0 |
| -5.0 | -5.0 |
| 0.0 | 0.0 |
| 5.0 | 5.0 |
| 10.0 | 10.0 |
| 15.0 | 15.0 |
| 20.0 | 20.0 |
| 25.0 | 25.0 |
| 30.0 | 30.0 |
| 35.0 | 35.0 |
| 40.0 | 40.0 |
Related Conversion Questions
- How many lux does 15 lumens produce over 2 square meters?
- What is the lux value for 15 lumens spread across 0.75 m²?
- Is 15 lumens brighter than 15 lux?
- How to calculate lux from 15 lumens if surface area is unknown?
- Can 15 lumens equal 15 lux for bigger areas?
- What surface area makes 15 lumens equal to 10 lux?
- Does 15 lumens always convert directly to 15 lux?
Conversion Definitions
Lumens: Lumens measures the total amount of visible light emitted by a source. It quantifies the brightness perceived by the human eye, regardless of direction. A higher lumen count means a brighter light output, useful in comparing bulbs or lamps.
Lux: Lux measures illuminance, or how much light lands on a surface area, measured in lumens per square meter. It describes brightness as perceived on surfaces, important for lighting design and ensuring adequate visibility.
Conversion FAQs
Can lumens be directly converted to lux without knowing the surface area?
No, lumens measure total light output while lux measures light intensity over area. Without knowing the illuminated surface size, converting lumens to lux is impossible because lux depends on how spread out the light is.
Why can lux sometimes be greater than lumens?
Lux can be higher when lumens are focused onto a smaller surface area. For example, 15 lumens over 0.5 m² equals 30 lux, which is greater because the light is concentrated, increasing illuminance.
Is it possible to have negative lux or lumens?
Negative values for lumens or lux don’t exist physically, as light can’t have negative brightness. Negative values might appear in calculations or graphs but do not represent real-world light measurements.
Does changing the distance between the light source and surface affect lux?
Yes, moving the light source farther away spreads the lumens over a larger area, reducing lux. Conversely, closer distance focuses lumens on smaller area, increasing lux.
How accurate is using 1 square meter as area for converting lumens to lux?
Using 1 m² area simplifies conversion because lux equals lumens in that case. However, real-world lighting rarely covers exactly 1 m² so results are estimations unless actual surface size is known.
