ForceField Tool: Generate CHARMM/NAMD Force-Field Parameters from a Structure

About

ForceField Tool takes a single molecular structure and produces a complete, simulation-ready CHARMM/NAMD parameter set: a topology file (.inp), force-field parameters (prms.prm), and a PSF/PDB pair generated with psfgen, plus a minimized structure. Atom types are assigned by connectivity-based similarity matching against the selected CHARMM force field.

Instructions

  1. Prepare your structure: a single molecule in PDB, mol2, or SDF format (with 3D coordinates).
  2. Choose a force field: pick the CHARMM dataset that matches your molecule (e.g. carbohydrate, protein, lipid, nucleic acid, or general/drug-like CGenFF).
  3. Upload & run: submit the form below. Processing runs on AWS and typically takes a couple of minutes.
  4. Download: when finished, download a ZIP containing the topology, parameter, PSF/PDB, minimized structure, and a report of any approximated parameters.

Note: results are cached, so re-submitting the same structure and force field returns instantly.

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ForceField Tool

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