These lists are based on the sixth edition of Chronologisch-thematisches Verzeichnis sämtlicher Tonwerke Wolfgang Amadé Mozarts (Chronological-Thematic Catalog of the Complete Works of Wolfgang AmadÈ Mozart), published in 1964. That information has been checked against more recent sources, chiefly The New Grove Mozart by Stanley Sadie. Works deemed spurious or doubtful have been deleted, as have most fragments and works that are considered lost.
Numbers from the first (K1) and sixth (K6) editions of the Köchel catalog are clearly marked in these lists. In all other references, the Mozart Project uses the following convention: Whenever possible, the original, first-edition designation is used. If there is a distinct sixth-edition designation, that number is separated from the first by a slash. If there is no first-edition designation, then only the sixth-edition number is used.