The Symposium is one of Plato's finest literary achievements, an extended meditation on the nature of love set at a dinner party featuring prominent real-life Athenians such as the great comic dramatist Aristophanes, and the controversial political prodigy, Alcibiades.
Free Online Texts
Bacchicstage: Plato's Symposium. Translated by George Theodoridis (2015). English online text.
Gutenberg: Symposium by Plato, translated by Benjamin Jowett, multiple formats.
Internet Classics Archive; Symposium, translated by Benjamin Jowett, online text.
University of Adelaide (Internet Archive): The Symposium, translated by Benjamin Jowett. EPUB, HTML and MOBI formats.
Wikisource: Symposium, translated by Benjamin Jowett (1871), online text.
BBC In Our Time: Plato's Symposium - radio discussion with Melvyn Bragg.
History of Philosophy without any gaps: Wings of Desire: Plato's Erotic Dialogues - podcast by philosopher Peter Adamson.
History of Philosophy without any gaps: Frisbee Sheffield on Platonic Love - podcast by philosopher Peter Adamson.
Librivox: The Symposium - audiobook.
Open Culture: The Drinking Party, 1965 Film Adapts Plato’s Symposium to Modern Times - video (embedded above).
Philosophy Bites: Angie Hobbs on Plato on Erotic Love.
YouTube: Diotima's Ladder - From Lust to Morality - Illustrated talk from BBC Radio 4's A History of Ideas narrated by Harry Shearer and scripted by Nigel Warburton.
YouTube: What is Love - The Myth of the Missing Half - Illustrated talk from BBC Radio 4's A History of Ideas narrated by Aidan Turner and scripted by Nigel Warburton.
Approaching Plato: A Guide to the Early and Middle Dialogues.
PhilPapers: Plato - Symposium - bibliography with open source option.
Stanford Encyclopedia of Philosophy: Plato on Friendship and Eros, by C.D.C. Reeve.
Wikipedia: Symposium (Plato).
The Great Conversation: Further reading at Tom's Learning Notes
Ancient Greek resources: Learn to read Greek classics in the original.
Bloom's Western Canon: Plato's Dialogues are listed.