The pyIAST package was developed with the idea that mixture isotherms are computed directly from the experimental (or simulated) pure component isotherms, without the need for any fitting. In our workflow to compute the pure component isotherms, we have ensured that we obtain adsorption isotherms up to 90% of the saturation loading, where we estimate the saturation loading from the pore volume. However, experimentally, in particular for N 2 , one often has isotherms that have been measured up to a maximum pressure that is far from saturation. In the case of such an incomplete isotherm, one has to be careful with pyIAST.