The Open Forcefield Toolkit provides implementations of the SMIRNOFF format, parameterization engine, and other tools. Documentation available at http://open-forcefield-toolkit.readthedocs.io

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• Updated Jul 27, 2026
• Python

Automated tools for the generation of bespoke SMIRNOFF format parameters for individual molecules.

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• Updated Jul 6, 2026
• Python

An automated framework for generating optimized partial charges for molecules

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• Updated Jul 6, 2026
• Python

OpenFF NAGL

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• Updated Jul 29, 2026
• Python

Force fields produced by the Open Force Field Initiative

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• Updated Jul 6, 2026
• Python

A project (and object) for storing, manipulating, and converting molecular mechanics data.

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• Updated Jul 27, 2026
• Python

CHARMM and AMBER forcefields for OpenMM (with small molecule support)

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• Updated Jul 13, 2026
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