Size a grow light from target PPFD and area.
Target intensity times canopy area yields total photon output, divided by fixture efficacy for wattage. PPFD and DLI are the scientific yardsticks for indoor growing, where guessing leaves crops leggy or scorched.
Grow Light PPFD
PPF = PPFD x area(m2); watts = PPF / efficacy; DLI = PPFD x hours x 0.0036
PPF = PPFD x area(m2); watts = PPF / efficacy; DLI = PPFD x hours x 0.0036 Target intensity times canopy area yields total photon output, divided by fixture efficacy for wattage.
PPFD and DLI are the scientific yardsticks for indoor growing, where guessing leaves crops leggy or scorched.
This calculator takes 4 inputs: Target PPFD, Canopy area, Light hours, Fixture efficacy. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.