How many popes have there been?

How to get close to this number

Divide the span by the average reign. The institution claims roughly two thousand years of continuous succession, and a papal reign averages somewhere around seven or eight years given that most popes are elected late in life. Two thousand divided by seven and a half gives a count in the mid-two-hundreds.

The reign lengths in the explanation show why the average is what it is: thirteen days at one extreme and thirty-one years at the other. Electing an elderly candidate is a long-standing feature of the system, which keeps average tenure short and the count correspondingly high for the timespan involved.

The count is also disputed at the edges. Early succession lists were compiled centuries after the fact, several periods had rival claimants, and the church has revised its own official numbering more than once. A figure like this comes from an institution counting its own history, which makes it authoritative and not quite the same thing as verified.