Winning Percentage

Winning Percentage is a statistic used both for teams and for pitchers.

For teams, it is calculated thus: (Games Won) / (Games Played)

For pitchers, the formula: (Wins)/(Wins + Losses)

All Time Leaders -- Pitchers
Span	Player	Total	Notes
Career (minimum 100 wins)	Spud Chandler	.717	109 wins
Career (minimum 200 wins)	Whitey Ford	.690	236 wins
Season (qualifier)	Johnny Allen	.938	1937
Season (no losses)	Tom Zachary	1.000	1929, 12-0

For teams, the highest winning percentage recorded since 1900 is .763, by the 1906 Chicago Cubs, who went 116-36. Since 1903, only 9 teams have played for a winning percentage of .700 or better, the last being the 2001 Seattle Mariners at .716.

Further Reading

• Douglas Jordan: "The .700 Club: Blessedly Good Baseball", The Baseball Research Journal, SABR, Volume 45, Number 2 (Fall 2016), pp. 26-33.
• John A. Richards: "Probabilities of Victory in Head-to-Head Team Matchups", The Baseball Research Journal, Vol. 43, number 2, Fall 2014, pp. 107-117.