* No central database: There's no single, universally agreed upon database that meticulously tracks every actor's film credits, especially those with careers as long as Jackson's.
* Cameos and uncredited roles: It's hard to count small cameos, voice roles, and uncredited appearances.
* Different sources, different numbers: Different online film databases and websites may have slightly different counts.
However, based on reputable sources, Samuel L. Jackson has appeared in well over 150 films.