Illuminance Converter

Illuminance is how much light falls on a surface. Lighting standards and light meters use lux (lumens per square metre) in most of the world and foot-candles (lumens per square foot) in the US. One foot-candle is about 10.764 lux. A bright office is around 500 lux; direct sunlight can exceed 100,000 lux.

How to use Illuminance Converter

1. Type the value you want to convert.
2. Choose the unit you have in From and the unit you want in To. The swap button turns the conversion round.
3. Read the answer, with the formula underneath. For example, 50 foot-candles ≈ 538 lux.
4. Open All units to see the value in every unit at once, and copy the one you need.

When it comes in handy

• Checking office, classroom or warehouse lighting against a standard.
• Setting up grow lights and photography lighting.
• Reading a light meter in a different unit.

Frequently asked questions

What is the difference between lux and lumens?

Lumens measure the total light a lamp gives out. Lux measures how much of it lands on each square metre. The same lamp gives fewer lux the further away the surface is.

How much light does a desk need?

Many office standards recommend about 300 to 500 lux on the desk surface.