OpenEye Scientific Software is an American software company founded by Anthony Nicholls in 1997. It develops large-scale molecular modelling applications and toolkits. Following OpenEye's acquisition by Cadence Design Systems for $500 million in September 2022, the company was rebranded to OpenEye Cadence Molecular Sciences and operates as a business unit under Cadence.

Primarily geared towards drug discovery and design, areas of application include conformation generation, docking, shape comparison, charge/electrostatics, cheminformatics and visualization. The software is designed for scientific rigor, as well as speed, scalability and platform independence.

OpenEye makes much of its technology available as toolkits suitable for custom development. The toolkits are available in multiple languages: C++, Python, Java and C#.^{[citation needed]}

Programming libraries providing wider applications with object-oriented accessibility to a given set of capabilities.