Chemistry at HARvard Macromolecular Mechanics

Welcome to the CHARMM Development Project

CHARMM Registration

CHARMM is a versatile molecular modeling and simulation program designed to provide broad capabilities for simulating many-particle systems, and includes a comprehensive set of force fields to simulate biomolecules, such as proteins, nucleic acids, carbohydrates, lipids, their assemblies, and the small molecules that interact with these targets.

CHARMM is designed to run on a variety of UNIX-compatible platforms, from high-performance parallel computers with integrated GPUs, to smaller GPU-based workstations. CHARMM can also utilize OpenMM GPU acceleration for MD simulations, which require NVIDIA’s CUDA 6.5 or newer libraries, NVIDIA GPU drivers, and OpenMM version 6.2 or greater. Running CHARMM in parallel requires FFTW (or Intel mkl) libraries, a recent version of MPI libraries, and one of the following supported compilers: GCC 4.8.3, Intel 14, PGI 2013 (or newer versions).

CHARMM is available to academic, government and nonprofit labs free of charge. CHARMM is also available to computing centers, provided that access is limited to academic or nonprofit users only; users need not have individual CHARMM licenses.

While we distribute CHARMM for academic, government and nonprofit use only, for-profit companies may contact BIOVIA, which distributes the commercial version, called CHARMm.

For more information on the CHARMM program, its capabilities and documentation, visit

To obtain the current version of CHARMM (v. 48), please register here.

For other inquiries, you may contact us by email.