This study presents a method to calculate the surface tension of a wide variety of organic carboxylic-based acids molecules starting from the experimental data of the liquid viscosity. The first step of this research was a data collection and then an accurate selection of experimental sources for the calculation of surface tension. Besides, in order to build two different but comparable databanks, the experimental points were regressed with simple equations at the same reduced temperature range, spanning from 0.35 to 0.75. As a final step, the original relationship of Pelofsky between the natural logarithm of surface tension and the inverse of viscosity was changed to better describe the property under investigation. The simple modification of adding the reduced temperature allowed to achieve an MD of 1.24% for the whole dataset that contains 22 fluids with 170 surface tension data and 379 liquid viscosity experimental data. (C) 2018 Elsevier B.V. All rights reserved.