The temperature coefficient, also known as Q10, quantifies the rate (R) increase of a reaction for every 10-degree temperature rise (T). The rate (R) can represent various measurements, such as the velocity of action potential propagation along a nerve fiber (e.g., m/s), the production rate of chemical reaction products (e.g., mmol/s), the current conducted through an ion channel, pump, or transporter (e.g., pA, nA, μA), or the heart contraction rate per minute (i.e., beats per minute, bpm). To determine Q10, the rate of the physiological process is measured at two temperatures, T1 and T2, where T2 is greater than T1, resulting in rate measurements R1 (at T1) and R2 (at T2). The Q10 equation (provided below) is then used to estimate the Q10 for the process. The temperature must be in Celsius or Kelvin and cannot be in Fahrenheit. It’s important to note that T1 and T2 do not have to be exactly 10 degrees apart for the equation to be applied. Additionally, the temperature unit for both T1 and T2 must be the same, as well as the unit for the rate measurements (R1 and R2). Q10 values are valuable as they offer insights into the underlying mechanisms of the physiological process being studied.

Temperature coefficient (Q₁₀) equation

• Q₁₀ is the factor by which the reaction rate increases when the temperature is raised by ten degrees. Q₁₀ is a unitless quantity.
• R₁ is the measured reaction rate at temperature T₁ (where T₁ < T₂). Note that R₁ and R₂ must have the same unit.
• R₂ is the measured reaction rate at temperature T₂ (where T₂ > T₁). Note that R₁ and R₂ must have the same unit.
• T₁ is the temperature at which the reaction rate R₁ is measured (where T₁ < T₂). The temperature unit must be either the Celsius or the Kelvin, and may not be any other unit, such as the Fahrenheit. Note that T₁ and T₂ must have the same unit. T₁ and T₂ do not need to be exactly 10 degrees apart.
• T₂ is the temperature at which the reaction rate R₂ is measured (where T₂ > T₁). The temperature unit must be either the Celsius or the Kelvin, and may not be any other unit, such as the Fahrenheit. Note that T₁ and T₂ must have the same unit. T₁ and T₂ do not need to be exactly 10 degrees apart.

Q₁₀ calculator