This paper describes a new digital approach to intertextual study involving the creation of a free online tool for the automatic detection of parallel phrases. A test comparison of Vergil’s Aeneid and Lucan’s Civil War shows that the tool can identify a substantial number of meaningful intertexts, both previously recorded and unrecorded. Analysis of these results demonstrates how automatic detection can provide more comprehensive and accessible perspectives on intertextuality as an aggregate phenomenon. Identification of the language features necessary to detect intertexts also provides a path toward improved automatic detection and more precise definitions of intertextuality.