The ZINC database is a free resource of purchasable compounds for virtual screening. It contains 727,842 molecules with 3D structures, assigned protonation states, and properties like molecular weight, LogP, and rotatable bonds. Each molecule includes vendor and purchasing information and is ready for docking. The database is available in formats like SMILES, mol2, 3D SDF, and DOCK flexibase. A web-based tool allows searching, browsing, and creating subsets. Users can upload their own molecules for processing. The database supports multiple protonation states, tautomers, stereochemistries, and conformations. It is designed for efficient loading, querying, and updates. The database includes subsets of molecules with varying properties, such as Lipinski-compliant, "lead-like," and "fragment-like" compounds. It is compatible with popular docking programs and provides molecular properties for analysis. The ZINC server allows users to upload and process their own molecules. The database is freely available and supports a wide range of molecular formats. It is intended for use by both experts and non-specialists in structural biology and medicinal chemistry. The database is continuously updated and includes a variety of purchasable compounds suitable for virtual screening.The ZINC database is a free resource of purchasable compounds for virtual screening. It contains 727,842 molecules with 3D structures, assigned protonation states, and properties like molecular weight, LogP, and rotatable bonds. Each molecule includes vendor and purchasing information and is ready for docking. The database is available in formats like SMILES, mol2, 3D SDF, and DOCK flexibase. A web-based tool allows searching, browsing, and creating subsets. Users can upload their own molecules for processing. The database supports multiple protonation states, tautomers, stereochemistries, and conformations. It is designed for efficient loading, querying, and updates. The database includes subsets of molecules with varying properties, such as Lipinski-compliant, "lead-like," and "fragment-like" compounds. It is compatible with popular docking programs and provides molecular properties for analysis. The ZINC server allows users to upload and process their own molecules. The database is freely available and supports a wide range of molecular formats. It is intended for use by both experts and non-specialists in structural biology and medicinal chemistry. The database is continuously updated and includes a variety of purchasable compounds suitable for virtual screening.