The impact of a uniform magnetic e eld on equilibrium combustion characteristics has been explored. An expression for the Gibbs free energy, which includes a magnetic e eld contribution, has been developed. Using the method of Lagrange multipliers, changes in the Gibbs free energy for a mixture of paramagnetic and diamagnetic ideal gases are minimized. A model reaction of methane in air is used to quantitatively examine the changes in equilibrium compositions in the presenceof a uniform magnetic e eld. Plots are presented showing theequilibrium mole fractions as a function of temperature and magnetic induction for all product species. In general, the results indicate that within certain temperature ranges a magnetic e eld decreases the mole fraction of major product species and increases the mole fraction of minor product species. The maximum equilibrium mole fraction of NO was observed to decrease an order of magnitude for an increase in magnetic induction of 0.00 ‐0.04 T. The impact of a magnetic e eld was seen to affect equilibrium combustion characteristics of NO at temperatures well above those existing in practical combustion applications.