The standings on the MLB web site refer to the magic number as the E#, E presumably standing for elimination. However, it turns out there isn't really a simple formula. That's because it's more complicated than comparing wins and losses of a particular team and the division (or wild card) leader. One also must take into account the games remaining between other teams in the division (or the wild card competition) that have not yet been eliminated. Here's an uncomplicated example. Say that there are two games left in the regular season. Teams A, B, and C are all in the same division. Team A and Team B have 90 wins and Team C has 88 wins. Team A and Team B play each other in their two remaining games. The MLB calculation would put Team C's E# at 1 because it is 2 games out with two games to play. However, because Team A and Team B play each other at least one of those teams will finish with 91 or 92 wins, meaning Team C is eliminated. To determine whether a team is eliminated from competition for a title one must determine the minimum possible wins for all other teams in contention and compare that to the maximum possible wins for the team in question. A loss by the team in question lowers the magic number by one, but because there are multiple teams involved a win by the team in first place does not necessarily lower the magic number by one. A side note: when I was attending The Ohio State University in the early '80's I learned from an acquaintance of a new definition for the term "Indian Summer". Cleveland baseball fans defined it as the period between the time their team was eliminated from postseason play and the end of the baseball season. Back in those years that Indian Summer usually lasted pretty long. (BTW, I almost always avoid using the nickname of the Cleveland and Atlanta baseball teams but it was necessary in this instance.)