chemfp is a set of command-lines tools for generating cheminformaticsfingerprints and searching those fingerprints by Tanimoto similarity,as well as a Python library which can be used to build new tools.These algorithms are designed for the dense, 100-10,000 bitfingerprints which occur in small-molecule/pharmaceuticalchemisty. The Tanimoto search algorithms are implemented in C forperformance and support both threshold and k-nearest searches.Fingerprint generation can be done either by extracting existingfingerprint data from an SD file or by using an existing chemistrytoolkit. chemfp supports the Python libraries from Open Babel,OpenEye, and RDKit toolkits.