The calculation of multiphoton ionization rates of the hydrogen molecular ion. We present the Floquet method of calculation of multiphoton ionization rates from the dressed σ g + and σ u + states of H 2 + . Our software allows a determination of ionization rates for a range of laser frequencies, intensities and internuclear separations. The theoretical method is discussed and instructions for use of the accompanying computer program, which also produces ionization rates for DC field ionization, are given.