The database enables search by structural similarity by comparing a user´s molecule to molecules in the BIOFACQUIM database. The "search by similarity" filter redirects users to a page where they can draw a molecule using the Molsoft plugin and upon clicking "search," a new gallery of molecules is generated, showing the most similar results along with the corresponding Tanimoto coefficient that is computed with the MACCS keys (166-bits) fingerprint. The results are ordered in descending order based on the similarity value (Figure ). The calculation of the MACCS keys and the Tanimoto coefficient are done with the RDKit python toolkit.