Greenhouse Light Calculator
Calculate Daily Light Integral (DLI mol/m²/day), required supplemental PPFD (μmol/m²/s), fixture counts, and daily electricity costs.
Photobiology Guide: Greenhouse Light & DLI Calculator
Light intensity and photoperiod duration govern crop growth velocity and yield potential. In controlled environment agriculture, overall light availability is measured as Daily Light Integral (DLI) in moles of light per square meter per day ($\text{mol/m}^2/\text{day}$). Using our greenhouse light calculator and dli calculator, growers can easily measure deficit light gaps and size supplemental LED grow light systems.
The Universal DLI and PPFD Equation
To convert Photosynthetic Photon Flux Density (PPFD in $\mu\text{mol/m}^2/\text{s}$) and photoperiod hours into DLI:
DLI (mol/m²/day) = PPFD (μmol/m²/s) × Photoperiod Hours × 3600 seconds / 1,000,000
Conversely, to calculate required supplemental PPFD needed to reach a target DLI:
Required PPFD (μmol/m²/s) = (Target DLI - Natural Solstice DLI) × 277.8 / Photoperiod Hours