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Lighting Calculator

Find out how many lumens your room needs and how many lamps or fixtures to install. The calculator uses typical illuminance levels by room type and adds a reserve for ceiling height.

Lighting Calculator

Calculate how many lumens you need and how many lamps to install based on room area and type.

Typical LED bulb: 800–1200 lm. Spotlights: 300–600 lm each.

10–15% for height and reflection loss.

Instructions
  1. Enter room length and width in meters.
  2. Select room type — the calculator uses standard lux norms (living 150, kitchen 250, office 300, etc.).
  3. Enter lumen per lamp (see packaging; typical LED bulb 800–1200 lm).
  4. Get total lumens and recommended number of lamps. Add 10–15% reserve for ceiling height.

Next step after lighting

Once the light level is set, the next practical step is usually palette work or the full room budget.

Area

Area = length × width in meters. Measure the room floor wall to wall.

Lux

Typical values: living room and bedroom 150 lux, kitchen 250, office 300, hallway 100.

Lumens per lamp

Check the packaging. A common LED bulb often delivers around 800–1000 lumens.

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