How much of Dragon Ball Z is not in the manga?
Dragon Ball Z ran 291 episodes, from 1989 to 1996, chasing a manga that was still being written, and its divergences come in two kinds. The first kind is the wholly anime original episode block, and it is countable. The largest is the Garlic Jr. arc, episodes 108 to 117, the only complete filler arc in the series, built around a villain who came from a film, not the manga. Before it, episodes 39 to 43 strand Bulma, Gohan, and Krillin on a fake Planet Namek built by stranded aliens. After it come the famous singles and small runs: episode 125, the driving test; episodes 195 to 199, the Other World Tournament and its anime original fighter Pikkon; episodes 202 to 204, the Great Saiyaman comedies; and late singles such as episode 274, inside Buu, and episode 287 to 288 material around the ending. Published filler lists, which differ at the edges, put the pure filler total at roughly 38 episodes, about thirteen percent, with a handful more counted as mixed.
The second kind is larger and harder to count: padding inside adapted material. The anime stretched the manga's fights with staring, charging, and reaction episodes, most notoriously around the Freeza battle, where episodes such as 100 and 102 are classed as filler inside a canonical fight. That is why the series feels slower than its filler percentage: the divergence is not mostly new story, it is the same story at lower speed. Toriyama, for his part, defended the arrangement in print during the run: the thirty minute episodes would quickly catch up to the manga, he wrote, so the anime staff inserted new material, work he praised while asking readers to enjoy both versions.
The cleanest proof of the ratio is what happened when Toei removed it. Dragon Ball Z Kai, the 2009 recut, tells the same manga story in 159 episodes in Japan by cutting most anime original material, which means roughly 130 episodes of Z were expansion of one kind or another, even though only about forty were wholly new stories. Both numbers are true. Z is a faithful adaptation with a slow pulse, and its invented episodes, the driving test above all, became some of its best loved.