Q10 Temperature Coefficient Calculator

Formel

How this is calculated

The Q10 temperature coefficient quantifies how sensitive a reaction rate — metabolic, enzymatic, or chemical — is to temperature. The formula Q10 = (R₂ / R₁)^(10 / ΔT) normalises the observed rate ratio to a standard 10 °C interval, allowing fair comparison between experiments at different temperature ranges. A Q10 near 1 indicates the rate is nearly temperature-independent (as for most physical diffusion processes); biological enzyme-catalysed reactions typically give Q10 ≈ 2–3, meaning the rate doubles or triples every 10 °C; Q10 values above 3 suggest the temperature is approaching an optimum or that regulatory effects dominate.

The rates R₁ and R₂ can be in any consistent unit — per second, per minute, μmol/min, oxygen consumption, ventilation rate — as long as both are in the same unit. The temperatures T₁ and T₂ are entered in degrees Celsius; the formula works identically in Kelvin since only the difference ΔT matters.

Limitations: Q10 assumes the ratio R₂/R₁ follows a simple exponential (van't Hoff rule). Real biological systems break this assumption near temperature extremes — below the thermal minimum or above the optimum — where enzymes denature or regulatory mechanisms cut in. Q10 should be treated as a local approximation valid over the measured temperature range, not as a globally constant property of the reaction.