Conspiracy theories explain the cause of world events through the machinations of shadowy, secret groups. Understanding what in conspiracy theories makes them appealing explanations is an important area of research. People like explanations that can account for a large number of seen events (broad explanatory scope), while not accounting for every possible unseen event (narrow latent scope). It is unknown if people think conspiracy theories have broad or narrow scope and how this may relate to their believability. We thus explored perceptions of conspiracy theory explanations’ scope and how this relates to their believability. Participants rated 40 conspiracy theories and their fact-based alternative explanations. Fact-based explanations were seen as having larger explanatory and latent scope. Additionally, larger scope was positively correlated with higher believability for both explanation types. We discuss how these findings relate to the explanation literature and highlight important elements of the seductive appeal of conspiracy theories.