Enter the temperature, rate coefficient, and constant. The activation energy calculator will evaluate and display the total activation energy.

Activation Energy Formula

The following equation can be used to calculate the activation energy of a reaction.

E = -R * T * ln(k/A)
  • Where E is the activation energy
  • R is the gas constant
  • T is the temperature
  • k is the rate coefficient
  • A is the constant

To calculate the activation energy, multiply the gas constant by the temperature, then multiply by the natural log of the ratio of the rate coefficient over the constant.

Activation Energy Definition

Activation Energy is the total energy needed for a chemical reaction to occur. It’s most often used in chemistry and thermodynamics. These reactions can include things like combustion.

Activation Energy Example

How to calculate an activation energy?

  1. First, determine the temperature.

    Measure the temperature of the substance.

  2. Next, determine the rate coefficient.

    Measure or calculate the rate coefficient.

  3. Next, determine the constant A.

    Empirically determine the constant A.

  4. Finally, calculate the activation energy.

    Using the formula above, calculate the activation energy.


What is an activation energy?

Activation energy is the total energy required for a chemical reaction to occur.