550 Lux to Lumen – Answer with Formula

550 lux corresponds to 550 lumens per square meter. To convert 550 lux to lumens, you multiply by the area in square meters that the light is spread across.

Lux measures illuminance, the amount of luminous flux per unit area, while lumen measures the total luminous flux emitted. Without knowing the area illuminated, lux can’t be directly converted to lumens. Assuming an area of 1 square meter, 550 lux equals 550 lumens.

Conversion Tool

Conversion Formula

The basic formula to convert lux to lumen is:

Lumen (lm) = Lux (lx) × Area (m²)

This formula works because lux measures luminous flux per unit area, so multiplying by the area gives the total luminous flux in lumens. If you know how much space the light covers, you can find total lumens by multiplying illuminance by that space’s size.

Example: If a surface of 2 square meters is lit with 550 lux, the total luminous flux is:

• 550 lx × 2 m² = 1100 lumens

This means the light source emits 1100 lumens over that 2 square meters area.

Conversion Example

• Example 1: 400 lux over 3 m²
  • Multiply 400 lux by 3 m²
  • 400 × 3 = 1200 lumens
  • The total luminous flux is 1200 lumens.
• Example 2: 1000 lux over 0.5 m²
  • 1000 × 0.5 = 500 lumens
  • This shows total light output for half a square meter.
• Example 3: 750 lux over 1.2 m²
  • 750 × 1.2 = 900 lumens
  • This is the total luminous flux for that area.
• Example 4: 300 lux over 4 m²
  • 300 × 4 = 1200 lumens
  • Total light emitted over 4 square meters.

Conversion Chart

This chart shows the direct conversion for lux to lumen when the area is exactly 1 square meter. To use it, pick your lux value from the left column and read off the equivalent lumen value on the right. For other areas, multiply accordingly.

Related Conversion Questions

• How many lumens equals 550 lux on a 2 square meter surface?
• What is the lumen output if 550 lux shines over 0.8 m²?
• Can 550 lux be converted to lumen without knowing the area?
• How does changing the area affect converting 550 lux to lumens?
• Is 550 lux equal to 550 lumens for any size area?
• What formula should I use to convert 550 lux to lumen?
• If I have 550 lux, how many lumens do I get on a 5 m² surface?

Conversion Definitions

Lux: Lux measures how much luminous flux falls on a surface per unit area. It is equal to one lumen per square meter. Lux tells you how bright the light appears on a surface, helping to understand light intensity distribution.

Lumen: Lumen measures the total amount of visible light emitted by a source. It quantifies the perceived brightness, regardless of the area over which the light spreads, showing overall light output.

Conversion FAQs

Can I convert lux to lumens without knowing the illuminated area?

No, lux measures light per unit area, so without knowing the size of the surface, you cannot find total lumens. You must multiply lux by the area in square meters to get lumens.

Why does the area affect conversion between lux and lumen?

Because lux is flux per unit area, changing the size of the illuminated surface changes the total luminous flux. More area means more total lumens for the same lux value.

Is 550 lux always equal to 550 lumens?

Only if the area is exactly 1 square meter. For other areas, the total lumens differ since lumens equal lux multiplied by area.

What if the surface is irregular or unevenly lit?

The conversion assumes uniform illuminance over the area. For irregular lighting, you need to calculate an average lux or measure total lumens directly.

How accurate is this conversion for practical lighting design?

The conversion is a theoretical calculation. Real-world factors like reflection, angle, and lamp efficiency affect actual illuminance and lumens received.