Paint Drying Time Calculator

Drying Time Calculation

Adjusted Time = Base Time × Thickness × Temperature × Humidity × Ventilation × Surface

Each medium has a base touch-dry, recoat and full-cure time at a 20°C, ~45% RH reference with normal ventilation on canvas. The factors then scale that base up or down. Warmer, drier, well-ventilated conditions with a thin film on a porous surface dry fastest.

The temperature factor follows the Arrhenius rule of thumb used for paint cure: drying roughly doubles for every 10°C above 20°C and halves for every 10°C below it (factor = 2^((20 − T) ÷ 10), clamped). The oil and oil-alkyd base times come from Winsor & Newton technical guidance — Artists' Oil Colour is touch-dry in 2–12 days in thin films (the fastest pigments around 2 days) and should cure roughly 6 months before varnishing, while Griffin Alkyd Fast Drying Oil Colour is touch-dry in 18–24 hours and varnishable in about 30 days.

The thickness, humidity, ventilation and surface multipliers are practical heuristics, not a manufacturer guarantee. Real drying depends on the specific pigment, medium, ground and airflow, so treat every figure as a planning estimate and test recoat or varnish readiness on a small area first.