ESPResSo (Extensible Simulation Package for Research on Soft Matter Systems) is a versatile molecular dynamics software package with a focus on coarse-grained models. Developed for both academic and industrial research, ESPResSo allows scientists and engineers to simulate multiphysics and multiscale problems with applications in soft matter research, statistical physics and process engineering. Some examples include models of energy materials, magnetic gels, biomolecules, and chemical reactions. The software is free, open-source, parallelized, and suitable for use on desktop machines, clusters, and supercomputers. Its flexible Python interface allows users to prototype advanced simulation protocols with relative ease, and to leverage scientific Python packages and molecular builders.

Specializing in molecular dynamics simulations, ESPResSo excels in bead-spring models, which are widely used in soft matter research. These models simplify complex systems by treating groups of atoms or molecules as single beads, enabling the study of larger systems over longer time scales. ESPResSo supports simulations in various statistical ensembles and non-equilibrium situations, incorporating advanced algorithms for hydrodynamic and electrostatic interactions. Developed and maintained primarily at the Institute for Computational Physics, University of Stuttgart, ESPResSo is used worldwide as both a production platform and a research tool for advancing simulation methods.