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Grow Room PPFD Calculator

Having the right light and the right amount of light in your grow room is crucial to obtaining the best yields at the lowest price.  Our App is powered from  data from integrated sphere and photo-goniometer testing combined with the results from industry leading software AGI32.

This is where the Y factor comes in, YPF and YPFD are the counterparts of PPF and PPFD, the Y stands for 'Yield'.   YPF would for example show the amount of light that is used by your plants compared to PPF that shows the amount of light outputted by your lamp.

Our app helps you accurately calculate all of these values and more to help you achieve the perfectly balanced growing environment.  You can use this app to accurately plan the different phases of your grow using the slider in conjunction with the lamps power level to allow for exactly the right amount of light in your area for your current grow period.

Calculate all the Metrics

Our Grow Room app calculates all the metrics you will every need for managing light in your grow room:

  1. Energy Consumption.
  2. PPF and average PPF.
  3. PPFD and average PPFD.
  4. DLI and average DLI.
  5. LPD and average LPD.
  6. BTU and average BTU.
  7. And of course efficacy.
Download from the APP Store
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Grow Room Config
Select a grow room

Calculate and Compare Average YPFD

Compare one lamp against another to see which is best for your room and plant type: 

  1. You can use our app to help plan your upcoming rooms. 
  2. Preset list of many lamps.
  3. Using the tools provided you can achieve huge energy savings in your grow rooms helping your pocket and the environment.
compared lamp
Action Spectrums

PPFD and YPFD Report Example

Accurately Calculating Average PPFD

Light uniformity is the most important factor for most growers either domestic or professional as there are no set benchmarks pertaining to exact spectrum's per plant species yet.

Whether you are growing with led, hps or CFL achieving the correct amount of average light for your plants in their current environment will allow you to achieve the results you require.

Total PPF output and efficacy are not good general indicators of how the lamp will perform in a grow room or glass house environment but are indicators as to the power output and efficiency of the lamps electrical factors.

AGI32 Example

Best Method = Use Maths


Average PPFD can only be calculated accurately using mathematical equations based upon photo-metric readings for the lamp from integrated spheres and goni-photometers (.ies files that any lamp manufacturer should be willing to make available).

Plants spectral requirements can of course vary but for most plants the requirements are approximately within the 400-700nm bandwidth.

If the SPD (spectral power distribution) of a light source is known then the photosynthetic energy available to plants can be calculated and a conversion factor determined to be used in calculating photosynthetic photon flux density in μmol/s-m2.

Average PPFD should be calculated using what has become industry standard software AGI32 , all leading horticultural lighting companies have adopted the use of this software and it has become industry standard due to its market leading features for horticulture.

Measurement planes should a suitable colour, reflectivity and transparency to simulate your plants canopy, we use: Dark green 5% reflective measurement plane to simulate the maximum light absorption from a plants canopy. 94% reflective walls.

This method will of course produce a lower results vs using a handheld meter to measure light in a grow tent due to the additional reflection of light back to the meter from the rooms surfaces vs the absorption of the light in a real life environment.

The exact conditions for your measurements planes and surfaces may vary from one environment and species to another and you may choose to set your own measurement conditions.

It is important when comparing led lamps output that you have information about the measurement method and environment so you can best assess what you consider to be the actual output vs other lamps. 

Measurement Plane Colour and Reflectivity

Many times you will see grids that have been measured in a reflective grow tent and these readings can be very misleading and will differ radically form real life readings.

It is important to benchamrk surface refletivity to around 5% dark green measurement plane and also on a 90% reflective light grey measurement plane to aschieve more life-like simulations.


Surface Colour