Calculators
Online Calculators - Light Measurement Unit Conversion Calculators
ILT is pleased to provide these free, easy-to-use calculators for converting between various light measurement units. Please visit our LIGHT METERS and LIGHT DETECTORS product pages if you need light measurement equipment. Finally, please download a FREE copy of the ILT LIGHT MEASUREMENT HANDBOOK.
Need Light Measurement Help? Click on THIS LINK to Email an ILT Light Measurement Expert
Beam Intensity Typical/Custom Measurement Range Calculator
This calculator will calculate typical beam intensity min/max ranges for a system you may be interested in purchasing based on your intended measurement distance to help determine if it will meet your measurement specifications/requirements. This calculator may also be used to calculate the min/max measurement ranges in beam intensity as well as new sensitivity factors to measure directly in beam intensity based on your existing systems sensitivity factor in foot-candles/lux.
Exposure Value (EV)/Lux Converter
Use this online calculator to convert exposure values (EV) to Lux and Lux to EV
Use this converter to either convert your Foot-Candle detector sensitivity factor to Lux or vice-versa for continuous measurement in the opposite unit or convert a single reading already taken in Foot-Candles to Lux or vice-versa.
Use this calculator to find out how an irradiance/illuminance measurement taken at a particular distance from a source will change as the distance to the source increases or decreases.
QNDS Self-Calibration Calculator
Use this calculator to obtain a new calibration sensitivity factor for a detector when a neutral density filter (QNDS1, QNDS2 OR QNDS3) is added to the assembly in the field.
Lux or Foot-candles to Total Lumens Converter
Use this online calculator to calculate the approximate total lumen output of a light source based on measurements taken in Lux or Foot-candles at a specific distance. Please note that this is a geometry conversion and and can only be used to get the APPROXIMATE total lumen output.
Watts/m2 or W/cm2 to Total Watts Converter
Use this online calculator to calculate the approximate total watt output (optical power) of a light source based on irradiance measurements taken in W/m2 or W/cm2 at a specific distance. Please note that this is a geometry conversion and and can only be used to get the APPROXIMATE total watt output (optical power).
µMoles (µEinsteins) / Lux Converter
Use this online calculator to convert µMoles (µEinsteins) which is Photosynthetic Photon Flux (PPF) to Lux (illuminance) or Lux to PPF based on the measurements taken and the type of light source.



