Unit Conversion

Convert numbers between two units quickly and precisely

Luminous Flux

Unit Conversion

Convert luminous flux: lumen and kilolumen

Luminous flux states the total amount of visible light emitted by a light source and is stated in lumen (lm), the SI unit, as well as kilolumen (klm) for very bright sources.

Key conversion factors:

  • 1 kilolumen (klm) = 1,000 lumen (lm)
  • Incandescent bulb, 60 W: approx. 700 lumen · LED lamp, 10 W: approx. 800 lumen

Applications:

  • Lighting technology: stating the total brightness of lamps and luminaires
  • Energy efficiency: comparing classic incandescent bulbs with LED lamps in lumen per watt

The luminous flux converter supports comparing light sources and planning lighting concepts. For illuminance on a specific surface, use the illuminance converter.

Frequently asked questions about converting luminous flux

A 10-watt LED bulb delivers about 800 lumens, comparable to a classic 60-watt incandescent bulb, which also reaches about 700 lumens. The big difference is energy efficiency: the LED produces a similar amount of light with much less power consumption.

Kilolumen (klm, 1 klm = 1,000 lm) is used for very bright light sources, such as floodlights, projectors, or streetlights, where pure lumen figures would result in unwieldy large numbers.

No. Watt describes a lamp's power consumption, while lumen describes the actual amount of light emitted. Since different lamp types (incandescent, LED, halogen) produce different amounts of light at the same power consumption, a direct comparison only makes sense via lumens, not watts.