Pitching Stats 101

Measuring pitching has also been one of the most common statistics used and earned run averages can be found in newspapers from the early 1900's! The following formulas, descriptions and statistics will provide you with the common and not-so-common items currently being used to measure pitching performance in the major leagues today.

"Don't throw the ball; push it towards home plate with a stiff wrist out of your usual motion. Imagine you are tossing a pair of socks into the hamper." - Bill 'Spaceman' Lee
Pitching Stats 101

Formulas / Definitions / Examples


(Innings Pitched divided by 9) x (League ERA - ERA)

An advanced pitching statistic used to measure the number of runs a pitcher prevents from scoring compared to the league's average pitcher in a neutral park in the same amount of innings. This is similar to the ERA+ statistic listed below and acts as a quantitative counterpart.


(Number of Earned Runs x 9) divided by (Number of Innings Pitched)

One of the oldest pitching statistics that is the most commonly used and understood in the Major Leagues today. Virtually every fan knows what it means but many often forget the formula used to compute the pitchers ERA. It originally appeared in the early 1900's and when calculating, remember not to add those runs which scored unearned. Need to know what is & is not an Earned Run?


League ERA (divided by) ERA

This statistic uses a league normalized earned run average in the calculation and is meant to measure how well the pitcher prevented runs from scoring relative to the rest of the league. It is a similar to the hitter's PRO statistic and when calculated the decimal is also dropped here.


Start with 50 points. Add 1 point for each out recorded, (3 points per inning). Add 2 points for each inning completed after the 4th. Add 1 point for each strikeout. Subtract 2 points for each hit allowed. Subtract 4 points for each earned run allowed. Subtract 2 points for each unearned run allowed. Subtract 1 point for each walk.

An advanced pitching statistic developed by Bill James used to measure how dominant a pitcher performed in each game he pitched. Often referred to as "Ryanicity" since Nolan Ryan and his multiple no-hitters were amongst the best Game Scores ever recorded until Kerry Wood threw his twenty strikeout game in 1998. The strikeouts in that game combined with the lack of hits (1) made it better than a perfect game as the statistics rewards dominance (strikes) and lack of hits while penalizing for walks.


Number Of Allowed Hits (divided by) (Batters Faced - Walks - Hit Batsmen - Sacrifice Hits - Sacrifice Flies - Catcher's Interference)

Another common statistic in baseball and also quite easy to understand and easy to compute. The primary purpose for this measurement is to gauge the opposing team's batting average when facing this particular pitcher in the game currently being pitched.


(Hits + Walks) divided by Innings Pitched

An extremely popular statistic that is primarily used and discussed with the Fantasy Leagues and Rotisserie Leagues. Developed to measure the approximate numbers of walks and hits a pitcher allows in each inning he pitches then compares the value received to other pitchers to formulate a pitcher's index.


Number of Wins (divided by) Number of Decisions

Another common statistic in baseball and also quite easy to understand and easy to compute. The primary purpose for this measurement is to gauge the percentage of a pitcher's games that are won.

This pitching term was created by the people at USA Today and awards a relief pitcher who preserves the lead by not allowing any runs (earned or unearned) and passes it on to another pitcher for a save opportunity.

A pitcher can earn a save by completing ALL three of the following items:

  1. Finishes the game won by his team.
  2. Does not receive the win.
  3. Meets one of the following three items:
    1. Enters the game with a lead of no more than three runs and pitches at least one inning.
    2. Enters the game with the tying run either on base, at bat, or on deck.
    3. Pitches effectively for at least three innings.
Pitching Statistics


Ed Walsh pitched from 1904 through 1917. Thirteen years of big league pitching and his lifetime earned run average (click link for top 100) is the lowest in the league 1.82.

Winning percentage, earned run average and saves are the only pitching statistics an average fan probably ever need to truly understand & follow our national pastime.

Did you know that Kerry Wood of the Chicago Cubs had a game score of 105 during his twenty strikeout game — one of the highest recorded game scores to date.