Mean Kinetic Temperature (MKT)

Mean Kinetic Temperature (MKT) is a single calculated temperature value that represents the overall effect of temperature fluctuations during storage or transportation. Unlike a simple average, MKT accounts for the Arrhenius equation — giving more weight to higher temperatures because heat-driven degradation accelerates exponentially with temperature.

MKT is defined by the International Council for Harmonisation (ICH) guideline Q1A and the United States Pharmacopeia (USP) <1150>. It is the standard method for evaluating whether temperature-sensitive products (especially pharmaceuticals) have been adequately stored.

A simple average temperature can be misleading. If a product was stored at 2°C for 23 hours and at 25°C for 1 hour, the average is 3°C — which looks fine. But the MKT would be significantly higher, revealing that the brief high-temperature event caused more degradation than the average suggests. MKT gives a true picture of thermal stress.