Your player comes home talking about their OPS and you smile and nod. Here's what every number on the stat sheet actually means: the formula, and more importantly, what it tells you about how your child is developing.
| Abbreviation | Stat | Formula | What it tells you |
|---|---|---|---|
| AVG | Batting average | H ÷ AB | How often an at-bat ends in a hit. Ignores walks, so patient hitters look worse than they are. Calculator. |
| OBP | On-base percentage | (H + BB + HBP) ÷ (AB + BB + HBP + SF) | How often the player reaches base by any means. Many coaches value this above AVG. Calculator. |
| SLG | Slugging percentage | Total bases ÷ AB | Power. A single counts 1, a double 2, a triple 3, a home run 4. Calculator. |
| OPS | On-base plus slugging | OBP + SLG | The all-in-one hitting number. Above .800 is strong in the majors. Calculator. |
| Abbreviation | Stat | Formula | What it tells you |
|---|---|---|---|
| ERA | Earned run average | (ER × innings per game) ÷ IP | Earned runs allowed per full game. Runs that scored on errors don't count. Calculator. |
| WHIP | Walks + hits per inning | (BB + H) ÷ IP | Baserunners allowed per inning: a clean read on command. Calculator. |
| K/BB | Strikeout-to-walk ratio | K ÷ BB | Missing bats without giving away free bases. A rising K/BB usually means real progress. |
| Abbreviation | Stat | Formula | What it tells you |
|---|---|---|---|
| FLD% | Fielding percentage | (PO + A) ÷ (PO + A + E) | Share of chances handled cleanly. Doesn't reward range, so a player who reaches more balls may show more errors. |
For a growing player, a single game's line means very little. What tells the real story is the direction over weeks and seasons. Is the average climbing? Are walks going up? Is the ERA coming down? That's the view a season-long tracker gives you that a one-game stat sheet can't.
Batting average (AVG) = hits ÷ at-bats. Walks and hit-by-pitch don't count as at-bats, so they don't lower it. A .300 average means the player got a hit in 30% of their at-bats.
Batting average only counts hits. On-base percentage (OBP) also credits walks and hit-by-pitch, so it measures how often a player reaches base at all — often a better sign of a productive hitter.
ERA measures earned runs allowed per full game. 'Good' varies enormously by age and league, so watch the trend over a season rather than chasing a single number. For context, an ERA under 3.00 is considered strong in Major League Baseball.