Plant Grow Light Intensity Calculator – Calculate Recommended Light Intensity for Plants

Best Light Intensity

Note:If recommended Growing Lamp Intensity is larger than Max Lighting Intensity, it means the lighting intensity is too strong for your plant under your input hours. To solve it, you need to make your lighting hours longer, so that you will get smaller Growing Lamp Intensity.
  • Plant:
  • Lighting Hours:

  • Recommended Min Lighting Intensity (μmol/s/m²):
  • Recommended Max Lighting Intensity (μmol/s/m²):
  • Recommended Growing Lamp Intensity (μmol/s/m² at 1FT):
Plant Grow Light Intensity Calculator – Calculate Recommended Light Intensity for Plants

Plant Grow Light Intensity Calculator – Calculate Recommended Light Intensity for Plants

If you’re growing plants indoors or in controlled environments, choosing the right grow light intensity is critical for healthy and productive growth. Our Plant Grow Light Intensity Calculator helps you calculate the recommended μmol/s/m² @ 1FT light output. The calculation is based on scientifically backed data from a plant light requirement database.


How does it work? This function uses the optimal PPFD (Photosynthetic Photon Flux Density) and DLI (Daily Light Integral) ranges for different plant species. As the input, you enter the plant’s name and specify the number of lighting hours per day (e.g., 12 hours). Then the calculator finds the required PPFD intensity to meet the plant’s average DLI target over the specified lighting duration.


This approach ensures that you provide enough light energy throughout the day, even if the lighting period is constrained. The output includes a recommended PPFD target (μmol/s/m² @ 1FT), which you can use to evaluate or select grow lights for your plant setup.


Important: This function requires both plant_name and target_hours as input. Without both inputs, the calculation will not execute.


This tool is especially useful for indoor gardeners, greenhouse operators, vertical farms, and home hobbyists who want to optimize light levels based on species-specific requirements. By calculating the proper light intensity, you can prevent under-lighting, reduce electricity costs, and improve yield and plant health.