ONE FORMULA, ONE ANSWER
Arrhenius Rate Constant Calculator
Check the temperature dependence of a reaction rate constant. Choose input units and calculate one value within the stated conditions.
Inputs
Calculations run in this browser. Scientific notation such as 1.2e-3 is supported. Do not group thousands.
Result
Arrhenius rate constant k
Enter values and select Calculate.
k = A exp(−E_a / (R T))
Assumptions
Use A,T>0 within a reaction and temperature range where A and E_a can be treated as constant. The units of k depend on reaction order and match the chosen A unit; they are not always s⁻¹. Convert kJ/mol to J/mol.
Displayed values are floating-point approximations. Measurement uncertainty and design safety factors are not calculated.
Formula references and credits
NaNa Lab created the code, descriptions, icons and preview images. Text, figures and code from the linked references have not been reproduced.
Physical constants: NIST / CODATA 2022. The values of μ₀ and ε₀ are measured recommendations, not exact defining constants. Values and precision notes are in the source record.
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