Ockeghem's surviving musical output is relatively small, comprising a mere handful of motets, several masses, and a couple of dozen secular chansons. His style is marked by a careful handling of vocal ranges in a primarily four-voice texture, and an emphasis on complex and expressive bass lines. This emphasis on lower textures opened up a new world of structural possibilities for Renaissance composers, and Ockeghem's compositions exploit these potentials in a variety of ways.
Today he is best known for his masses and his ability to integrate large-scale forms in ways which were as unparalleled then as they are now. By the sixteenth century, Ockeghem was known primarily as an accomplished technical master, famous for his complex lines and polyphonic structures, which had the appearance of intractable puzzles for all but the most accomplished musicians. This perception of difficulty, as well as the unique texture of his works, is due in part to his emphasis on long lines which gradually unfold with the formal development of a piece - a development accomplished by a carefully executed structural plan which includes the supression of cadential features in one or more voices at otherwise "planned" cadences.
Ockeghem's reputation as a purely technical master was also earned by the relatively long survival of his more intricate polyphonic explorations as textbook sources. These include his incomparable "Missa Prolationum," constructed entirely in canon; his "Missa Cuiusvis toni," designed to be performable in any of the available modes (catholicon); and his chanson "Prenez sur moi," which is both a strict canon and a catholicon. However, Ockeghem's music is by no means dominated by these technical features (and even in these works, the result is astonishing); his contrapuntal language is extremely varied and complex, largely abandoning the simpler fauxbourdon style of Dufay, but not resting exclusively on the pervasive imitation characteristic of Josquin and the successive continental masters. Today, Ockeghem is regarded not only as one of the pioneers of Western polyphony, but as one of the supreme masters of both lyrical and contrapuntal invention.