Pharmit represents a significant advance over existing browser-based virtual screening servers. Among its virtues are its search speed, which is on the order of seconds; its high-resolution, smoothly animated visual interface; its customizability, including the capability to create custom compound libraries; and its expansive suite of search features, including an array of chemical constraints that allow the user to rapidly identify hits that are also promising drug candidates. It democratizes structure-based computer-aided drug discovery by offering free and open access to state-of-the-art software for exploring chemical space, making it ideal for research and education alike. Educators can deploy a high quality product to illustrate fundamental concepts in physical chemistry. Researchers can adapt the project to incorporate it into their existing drug discovery workflows. In settings where intellectual property protection is an issue, the entirely open source nature of Pharmit allows it to be deployed locally by the user, ensuring the complete privacy of queries and results. Pharmit anticipates the needs of the medicinal chemist by facilitating direct comparison between a search ligand and hits, permitting in-browser energy minimization, and enabling the user to rapidly launch new sessions using molecules found via a query. Pharmit enables the user to perform structure-based virtual screening in a manner that is fast and intuitive.