# Q10 (temperature coefficient)

The Q10 temperature coefficient is a measure of the rate of change of a biological or chemical system as a consequence of increasing the temperature by 10 °C. There are many examples where the Q10 is used, one being the calculation of the nerve conduction velocity and another being calculating the contraction velocity of muscle fibres. It can also be applied to chemical reactions and many other systems.

The Q10 is calculated as:

$Q_{10}=\left( \frac{R_2}{R_1} \right )^{10/(T_2-T_1) }$

where

R is the rate
T is the temperature in Celsius degrees or kelvins.

Q10 is a unitless quantity, as it is the factor by which a rate changes, and is a useful way to express the temperature dependence of a process.

For most biological systems, the Q10 value is ~ 2 to 3.[1]