MLB stat glossary
Every abbreviation in an NBA, NFL or MLB box score, with the formula behind it, this season’s league leaders and the median across qualified players, so a number has something to be measured against.
MLB58 terms
MLB leadersBatting
- Home RunsHRHome runs hit.
- RBIRuns that scored because of this batter's plate appearance.
- HitsHTimes the batter reached base by hitting the ball, without help from an error.
- RunsRTimes the player crossed home plate.
- Stolen BasesSBBases taken while the pitcher was delivering. Being caught is counted separately.
- Doubles2BHits that carried the batter to second base.
- Triples3BHits that carried the batter to third base.
- WalksBBTimes the batter reached first base on four balls.
- StrikeoutsSOTimes this batter struck out — lower is better.
- Sacrifice FliesSFFly-ball outs that let a runner score.
- Sacrifice HitsSHBunts that give up an out to move a runner up.
- Total BasesTBBases gained on hits: one for a single up to four for a home run.
- Extra-Base HitsXBHDoubles, triples and home runs together.
- Hit By PitchHBPTimes the batter was hit by a pitch and awarded first base.
- Intentional WalksIBBWalks the defense chose to give.
- Grounded Into Double PlayGIDPGround balls that became two outs.
- Caught StealingCSSteal attempts thrown out.
- At BatsABPlate appearances that ended in a hit or an out, walks and sacrifices aside.
- Plate AppearancesPAEvery trip to the plate, walks and sacrifices included.
Batting rates
- Batting AverageAVGHits per at-bat. .300 is the traditional line between a good hitter and a great one.
- OPSOn-base percentage plus slugging. Around .800 is All-Star level, .900 is MVP territory.
- On-Base %OBPShare of plate appearances that ended with the batter on base — hits, walks and hit-by-pitches.
- Slugging %SLGTotal bases per at-bat, so a home run counts four times a single.
- Isolated PowerISOPExtra bases per at-bat: slugging with the singles taken out. .200 is real power.
- Stolen Base PercentageSB%Share of steal attempts that succeeded.
- Secondary AverageSECABases gained beyond singles, from power, walks and steals, per at-bat.
- Pitches Per Plate AppearanceP/PAPitches the batter saw per trip to the plate.
- Walks Per StrikeoutBB/KWalks drawn for every strikeout.
- Walk RateBB/PAShare of plate appearances that ended in a walk.
- At-Bats Per Home RunAB/HRAt-bats needed per home run — lower means more power.
- Runs CreatedRCEstimate of the runs the batter’s hitting produced.
- Runs Created Per 27 OutsRC/27Runs a lineup of this batter would score in a full game.
Pitching
- ERAEarned runs allowed per nine innings pitched — lower is better. Under 3.00 is excellent.
- WHIPWalks and hits allowed per inning pitched — lower is better. Around 1.00 is elite.
- SavesSVGames finished by protecting a narrow lead to the last out.
- WinsWGames in which this pitcher was credited with the win.
- Strikeouts (Pitching)KBatters this pitcher struck out.
- Strikeouts Per 9 InningsK/9Strikeouts per nine innings pitched.
- Strikeout-to-Walk RatioK/BBStrikeouts for every walk issued. 3.0 is good, 5.0 is elite.
- Innings PitchedIPOuts recorded, in innings: 170.2 is 170 innings and two outs.
- Winning PercentageW%Share of a pitcher’s decisions that were wins.
- HoldsHLDRelief outings that protected a lead without finishing the game.
- Quality StartsQSStarts of six innings or more with three earned runs or fewer.
- Complete GamesCGGames the starter pitched from first out to last.
- ShutoutsSHOComplete games that allowed no runs.
- BalksBKIllegal pitching motions with runners on base.
- Wild PitchesWPPitches the catcher could not handle that let a runner advance.
- Game ScoreGSCBill James’s one-number grade of a start, averaged: 50 is ordinary.
- Total Batters FacedTBFPlate appearances against the pitcher.
- Opponent Batting AverageOBAThe batting average hitters managed against the pitcher.
- LossesLGames charged to the pitcher whose team fell behind for good.
- Inherited RunnersIRRunners already on base when the reliever came in.
- Inherited Runners ScoredIRSInherited runners who went on to score.
- Run SupportRSUPRuns his own team scored while he pitched.
- Batters HitBHBatters hit by one of his pitches.
- Opponent OPSOOPSOn-base plus slugging hitters managed against him.