MARSAC is an open-source framework coded in Python language that characterizes the anisotropic mechanical behavior of soft tissues. From an output video file gathered with the CutiScan® device during a ring suction test, MARSAC computes the displacement field using DIC and identifies the Langer’s line direction, as well as the elastic moduli along and across it, for a given Poisson’s ratio value. Every user of this code is cordially encouraged to reference the following paper: A. Elouneg, J. Chambert, A. Lejeune, Q. Lucot, E. Jacquet, S.P.A. Bordas, Anisotropic mechanical characterization of human skin by in vivo multi-axial ring suction test, Journal of the Mechanical Behavior of Biomedical Materials, Volume 141, 2023,105779, ISSN 1751-6161, https://doi.org/10.1016/j.jmbbm.2023.105779.