matscopy is a Python package for materials science at the atomic scale, providing tools for atomic-scale modeling and analysis. It supports applications in fracture, plasticity, tribology, and electrochemistry. The package connects atomic-scale simulations with continuum descriptions in mechanics and transport theory, enabling multi-scale modeling. It includes functions for computing elastic moduli, analyzing dislocations, and simulating fracture mechanics. matscopy also offers general utility functions such as efficient neighbor list calculations, atomic strain analysis, and correlation functions. It supports interatomic potentials and calculators for various physical models, including quantum mechanics/molecular mechanics and committee models. The package is designed to work with widely used simulation environments like ASE and LAMMPS, and provides tools for post-processing simulation data. matscopy is not designed for two-way coupled calculations but focuses on constructing atomic domains from continuum information and extracting continuum fields from atomic structures. It is used in studies of elasticity, plasticity, fracture mechanics, and tribology, and has applications in electrochemistry for modeling charged systems. The package is open-source and released under a Creative Commons Attribution 4.0 International License. It is developed by a team of researchers from various institutions and is supported by multiple funding bodies.matscopy is a Python package for materials science at the atomic scale, providing tools for atomic-scale modeling and analysis. It supports applications in fracture, plasticity, tribology, and electrochemistry. The package connects atomic-scale simulations with continuum descriptions in mechanics and transport theory, enabling multi-scale modeling. It includes functions for computing elastic moduli, analyzing dislocations, and simulating fracture mechanics. matscopy also offers general utility functions such as efficient neighbor list calculations, atomic strain analysis, and correlation functions. It supports interatomic potentials and calculators for various physical models, including quantum mechanics/molecular mechanics and committee models. The package is designed to work with widely used simulation environments like ASE and LAMMPS, and provides tools for post-processing simulation data. matscopy is not designed for two-way coupled calculations but focuses on constructing atomic domains from continuum information and extracting continuum fields from atomic structures. It is used in studies of elasticity, plasticity, fracture mechanics, and tribology, and has applications in electrochemistry for modeling charged systems. The package is open-source and released under a Creative Commons Attribution 4.0 International License. It is developed by a team of researchers from various institutions and is supported by multiple funding bodies.