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Illuminance Converter

Just pick a value and unit to instantly convert between lux, kilolux, foot-candles, phot, nox and other key illuminance units. A table shows every unit's value at once.

Input

Unit to convert from

Result

In lux (lx)

1lx

UnitSymbolValue
Luxlx1
Kiloluxklx0.001
Foot-candlefc0.092903
Photph0.0001
Noxnox1,000

How it works

  • Supports lux (lx) and kilolux (klx) as well as foot-candles (fc), phot (ph), and nox (nox). Just enter a value and pick the input unit to see the converted value for every unit in one table.
  • Conversions are based on the lux (lx). The entered value is first converted to lux, then divided back by each unit's defined conversion factor to compute the value in every unit.
  • One foot-candle (fc) is about 10.7639 lux. It equals one lumen per square foot and originally comes from the imperial system.
  • One phot (ph) is 10,000 lux and one nox (nox) is 0.001 lux. Phot is used for strong brightness, while nox describes dim, moonlight-level environments.
  • Illuminance measures the amount of light reaching a unit area. Typical office work runs around several hundred to 1,000 lux, while clear outdoor daylight is roughly tens of thousands to 100,000 lux.
  • Extremely large or small results are shown in exponential notation. Use these as practical estimates, and refer to measured values from instruments for precise lighting design.