VPD Calculator
Calculate vapour pressure deficit and dial in temperature & humidity for every growth stage
Air & Units
Leaf Temperature
Leaves transpire and sit cooler than the air — typically 1–3 °C below.
Measured canopy/leaf surface temperature (e.g. IR thermometer).
Target Range
Targets use leaf (canopy) VPD, the metric that matters to the plant.
Leaf VPD is the key number — aim for the green band for your stage.