Light exposure is not only important for seeing the world around us, it is also a key driver for health and well-being. The quantification of light, particularly in parameters relevant for humans, is subject to international consensus documents developed by the International Commission on Illumination (abbreviated as CIE = Commission Internationale de l’Eclairage). This includes quantities for the intensity of light exposure (e.g., illuminance, measured in lux) or indices of how well a light source renders colours (e.g., Rf). The CIE provides various spreadsheet-based tools for calculating these quantities from spectral measurements of radiant energy. Here, we present and discuss the open-source and open-access web platform luox, which was developed with researchers in mind to simplify the process of calculating relevant aspects of light exposures in experiments with human participants. We specifically focus on the challenges of translating written documents and equations into a web based platform using ES6 and ReactJS.