The present body of literature fails to adequately address the need for simulation metrics which determine the surface activity of target species in single or multi-solvent systems. Within this work a new property determinable by computational molecular dynamics simulation is detailed. That is the surface parameter, which is an indicator of the placement of a molecule with respect to the interface. Simulations were carried out on polyalkanes in alcohol co-solvated systems to verify systematically that the OPLS-AA force fields can accurately describe the solvation of low molecular weight polyalkanes with increased alcohol content. This parameter and the associated code are helpful in identifying quickly if a molecule is surface active, especially in mixed solvent systems. The code for the determination of this property is written in FORTRAN, a widespread and readily available package on most supercomputing systems where GROMACS is deployed. (C) 2015 Elsevier Ltd. All rights reserved.