WHIP is my all-time favorite baseball statistic. I’ll get into why in a bit. What WHIP measures is how many base runners a pitcher allows in an average inning. It’s a pretty easy way to calculate a pitcher’s effectiveness.

What elite pitchers in baseball have in common: low WHIP

what is whip in baseball

Over the course of his career, Walter Johnson’s WHIP was 1.061. That means he allowed 1.061 baserunners per inning. In his magical 1913 season, his WHIP was 0.780.

I independently discovered WHIP playing computer baseball in the mid-1980s. I played computer baseball a lot. There was no Internet, so there weren’t a lot of other things I could do with my computer. Not that I complained.

What I found was that elite pitchers had one thing in common. They didn’t allow a lot of base runners. The game I had didn’t calculate that, so I calculated it for every pitcher in the game, and if I wanted to give myself the best chance to win, whichever pitcher I had available with the best WHIP was the one I was going to put in the game.

I still lost sometimes, but not very often. That was a good thing too, because I hated losing.

Traditionally, WHIP isn’t one of the key statistics the people look at for pitchers. But it’s roughly equivalent to WAR for hitters, so it has started to gain favor in recent years.

What is a good WHIP in baseball?

The lower the better, because it means you’ve allowed fewer bass runners. Of course, every pitcher allows some base runners, so The number won’t be zero.

Realistically, if a pitcher has a WHIP below 1, that is a truly elite season. Even the best don’t do that every year. You can have a WHIP slightly above one and still be an all star, or even a Hall of Famer. Dwight Gooden posted a WHIP below 1 just once in his storied career, in his Cy Young-winning 1985 season. Nolan Ryan‘s best WHIP of his career was 1.006, in his age 44 season. Cy Young himself did it six times.

The problem with statistics that aren’t WHIP

Traditionally, we measure pitchers by earned run average, wins, and losses. But all of those statistics are problematic. Joe Morgan infamously said winds are the only statistic he cared about when it came to pitchers. A pitcher can either bring home the bacon or he can’t, he reasoned.

It sounds like one of those common sense solutions to a perplexing problem. But the trouble is, lots of factors beyond a pitcher’s control can influence that count. You can throw nine shut out innings, give up one run in the tenth, and lose. You can throw four shut out innings, leave the game for a pinch hitter, and not get the win because you didn’t pitch five innings. Whoever takes the mound after your team gets the lead we’ll get the win. Even if that pitcher only throws to one batter. It’s a dumb rule, but that’s the way the rule has been for more than a century.

Generally speaking, the good pitcher is going to win a lot of baseball games. But there are plenty of times getting credit for the win is about being in the right place at the right time.

Losses are also a poor measure. Nolan Ryan is a Hall of Fame pitcher. Guess what his average win-loss record was over his career? 14 wins, 13 losses. Nothing extraordinary. Baseball purists were fine with letting him in largely because he was able to perform at that level even at the age of 46. No one Ryan famously never won a Cy Young award. But in one of the seasons he was considered for that award, he had a losing record. When you are a good pitcher on a bad team, you can end up with a losing record.

Joe Morgan didn’t play on a lot of bad teams, so it’s understandable if he didn’t know that. But I’ll also argue that Joe Morgan was a much better player than he was an analyst. He could retort that I analyze because I couldn’t play, and he would have a point.

Earned run average

The third golden metric, besides wins and losses, is earned run average, which measures how many runs a pitcher gives up over the course of nine innings. This one is better, because the way you win games is by scoring more runs than your opponent. The fewer runs a pitcher typically gives up, the better a team’s chances of winning.

The problem with this one is pitchers rarely throw nine innings anymore. So it doesn’t really measure starting pitchers and relief pitchers the same way. It’s unfair to relievers.

The problem with WHIP

WHIP isn’t perfect either. There are pitchers who specialize in loading the bases and then striking out three batters in a row to end a game. These pitchers will have a lousy WHIP. I will also argue that formula doesn’t generally make for long and successful careers, but there are some pitchers who seem to have a knack for doing that successfully for a few years at least, and the math can’t explain it.

The bigger problem with WHIP is that it assumes that all base runners are the same, and evenly distributed. And neither is true. A home run is much more damaging than a walk. And with a runner on third base, a fly ball for an out can be more damaging than a walk. And WHIP doesn’t take that into account at all, but ERA does.

But WHIP works the same, no matter what a pitchers roll may be. It doesn’t care if you pitched one, two, five, or nine innings. It just counts how effective you were for whatever innings you did pitch.

The other problem is it doesn’t take hit batters into account. But hit batters are the rarest of the three types of base runners, and hit batters are caused by the same thing as walks, which is wildness. So WHIP still works as an estimate.

WHIP tends to fall apart as a statistic when hits come in bunches, but that’s sad, a pitcher with a low WHIP tends not to give up hits in bunches very often. A pitcher who does give up hits in bunches tends to end up with a high WHIP. That’s the nature of the game coming into play. If a pitcher does start giving up hits in bunches, the manager has a tendency to bring someone else in to try to minimize the damage.

It’s not a perfect statistic, but it’s almost as easy to calculate as ERA, and the statistics you need to calculate it, inexpensed, hits allowed, and walks aloud, tend to be readily available. And even if you don’t have a calculator available, you can start to calculate it in your head at the ballpark using the stats that are virtually guaranteed to be on the scoreboard, and recognize someone who’s doing really well when you see it. If you add up the hits and walks, and it’s less than a number of innings pitched, it’s a good sign for the pitcher.