basic

Arrhenius Pre-Exponential Factor A from k, Ea, and T Calculator

A = k · exp(Ea / RT).

Compute the Arrhenius pre-exponential (frequency) factor A given a measured rate constant k at temperature T and the activation energy Ea: A = k · exp(Ea / R·T). Uses R = 8.31446 J·mol⁻¹·K⁻¹. A has the same units as k and represents the rate when the activation barrier is overcome by all collisions.

Dr. Helena Ortiz By Dr. Helena Ortiz
Published Last reviewed 1 min read

Inputs

kJ/mol
K

Results

Enter values and click Calculate to see results.
Was this helpful?

How to use this calculator

  1. Fill in the inputs above using the units you already have.
  2. Values update automatically as you type — no submit button needed.
  3. Hover any result row for the underlying formula and intermediate values.

Formula

A = k · exp(Ea / R·T).

In depth

Compute the Arrhenius pre-exponential (frequency) factor A given a measured rate constant k at temperature T and the activation energy Ea: A = k · exp(Ea / R·T). Uses R = 8.31446 J·mol⁻¹·K⁻¹. A has the same units as k and represents the rate when the activation barrier is overcome by all collisions.