What Is WHIP in Baseball? Formula, Examples and What Is Good

WHIP in baseball stands for walks plus hits per inning pitched: add up the walks and hits a pitcher allowed, then divide by his innings pitched. A pitcher who gives up 150 hits and 50 walks in 180 innings has a WHIP of 200 / 180 = 1.11, meaning he let about 1.1 batters reach base per inning through hits and walks.

It is one of the quickest ways to see how much traffic a pitcher allows, and it sits next to ERA on almost every stat page and broadcast graphic. The math is easy once you know how to read innings pitched, because a box score that says 6.1 does not mean six and one tenth. This guide shows the formula, works through several examples with every step visible, explains what a good WHIP looks like, and covers what the stat quietly leaves out.

The WHIP formula

The formula has three ingredients:

WHIP = (walks + hits) / innings pitched

• Walks (BB, short for bases on balls): every batter the pitcher walked
• Hits (H): every hit allowed, from a bloop single to a home run, each counted once
• Innings pitched (IP): outs recorded divided by three, so partial innings count as thirds

Lower is better, and WHIP is normally shown to two decimal places. A 1.00 WHIP means one baserunner per inning from hits and walks; a 1.50 WHIP means three such baserunners every two innings.

The stat began in fantasy baseball, not in a front office. According to MLB.com's glossary, Daniel Okrent, the writer who invented rotisserie league baseball, coined it in 1979 and first called it innings pitched ratio before the name WHIP took over. It is still a standard pitching category in many rotisserie leagues. MLB's own glossary treats WHIP as an unofficial stat, meaning it is not one of the figures defined in the scoring rules of the Official Baseball Rules, even though MLB.com publishes WHIP leaderboards every season.

Reading innings pitched: .1 and .2 are thirds

Every out a pitcher records is one third of an inning. Box scores print those thirds with a shorthand where the digit after the dot counts extra outs, not tenths:

• 6.0 means 6 full innings, or 18 outs
• 6.1 means 6 1/3 innings, or 19 outs, which is 6.333 as a true decimal
• 6.2 means 6 2/3 innings, or 20 outs, which is 6.667 as a true decimal
• There is no 6.3, because the third out completes the inning and the total becomes 7.0

Convert before you divide. If you would rather skip decimals altogether, count outs and use this equivalent version:

WHIP = (walks + hits) x 3 / outs

The same shorthand trips people up with ERA, and our guide to ERA in baseball uses the outs trick in the same way.

Worked examples, step by step

All the pitchers in this section are hypothetical. The point is the arithmetic, so each example is checked two ways.

A single start: 6.1 innings, 5 hits, 2 walks

Add the baserunners: 5 hits + 2 walks = 7. Convert the innings: 6.1 means 6 1/3, or 6.333. Divide: 7 / 6.333 = 1.105, which rounds to a 1.11 WHIP for the start.

Outs check: 6.1 innings is 6 x 3 + 1 = 19 outs. Then 7 x 3 = 21, and 21 / 19 = 1.105. Same answer.

A full season: 172.2 innings, 158 hits, 48 walks

Baserunners: 158 + 48 = 206. Innings: 172.2 means 172 2/3, or 172.667. Divide: 206 / 172.667 = 1.193, which rounds to 1.19.

Outs check: 172 x 3 + 2 = 518 outs. Then 206 x 3 = 618, and 618 / 518 = 1.193. Same answer again.

A reliever: one bad night and one good season

A reliever records two outs, so 0.2 innings, and allows 2 hits and 1 walk. That is 3 baserunners in 2/3 of an inning: 3 / 0.667 = 4.50. Outs check: 3 x 3 = 9, and 9 / 2 = 4.50.

Over a full season the same reliever finishes with 64.1 innings, 45 hits and 22 walks. Baserunners: 45 + 22 = 67. Innings: 64 1/3, or 64.333. WHIP: 67 / 64.333 = 1.041, or 1.04. Outs check: 64 x 3 + 1 = 193 outs, and 67 x 3 = 201, so 201 / 193 = 1.041.

The contrast is the lesson. A single short outing can produce a wild WHIP, so a reliever's number means little until he has thrown a meaningful number of innings.

The mistake to avoid

Type the box score figure straight into a calculator and you treat 6.1 as six and one tenth. For the single start, 7 / 6.1 = 1.148, which rounds to 1.15 instead of the correct 1.11. Over the season the error shrinks, because the fraction is a smaller share of the total: 206 / 172.2 = 1.196, or 1.20 instead of 1.19. Small, but wrong, and enough to reorder a tight leaderboard.

Work out any WHIP below. Type innings pitched the way a box score prints them, such as 6.1 or 172.2, and the thirds are converted for you.

What counts as a good WHIP

There is no official scale, and league-wide WHIP moves from year to year. The rule-of-thumb chart in the FanGraphs stat library is a fair starting point:

• 1.00: excellent
• 1.10: great
• 1.20: above average
• 1.30: average
• 1.40: below average
• 1.50: poor
• 1.60: awful

By that chart, the 1.19 season above is a little better than above average, and the reliever's 1.04 is close to excellent.

For a sense of the extreme, the National Baseball Hall of Fame describes Pedro Martinez's 2000 season with the Boston Red Sox as the best single-season WHIP in big league history among pitchers who qualified for the ERA title. He allowed 128 hits and 32 walks in 217 innings: 128 + 32 = 160, and 160 / 217 = 0.737. That is roughly three baserunners every four innings across a full season.

WHIP vs ERA

ERA counts the earned runs a pitcher allows per nine innings. WHIP counts the baserunners he allows per inning through hits and walks. One measures the result, the other measures the traffic that usually leads to it.

The two usually move together, because more baserunners tend to mean more runs, but they can split. Picture two hypothetical starters who each throw 180 innings and allow 200 hits plus walks, so both have the same 200 / 180 = 1.11 WHIP. The first gives up 12 home runs, the second gives up 30. The second pitcher's baserunners do far more damage, and his ERA will almost certainly be higher, yet WHIP rates them identically.

Timing matters too. A pitcher who scatters his walks and hits across different innings, or escapes jams with double plays, can carry a much better ERA than his WHIP suggests. FanGraphs makes a related point in WHIP's favor: because it is built from individual events rather than the order they happen in, it is less tied to that kind of sequencing than ERA is. That is why many fans read the two side by side rather than choosing one.

What WHIP leaves out

WHIP only counts two ways of reaching base. MLB.com's glossary notes that hit batters, errors and fielder's choice plays are not counted against the pitcher. Here is what that means in practice:

• Hit by pitch: a hit batter reaches base just like a walk, but WHIP ignores him
• Errors: a batter who reaches on a fielding error does not count, even though he is a real baserunner
• Fielder's choice: if the batter is safe because the defense got another runner out instead, WHIP adds no baserunner
• Type of hit: a home run counts exactly the same as a single
• Defense: whether a ground ball becomes a hit depends partly on the fielders, so a pitcher with a poor defense behind him will see his WHIP climb

The hit batter gap is easy to see with numbers. A hypothetical starter throws 180 innings and allows 140 hits, 40 walks and 15 hit batters. His WHIP is (140 + 40) / 180 = 180 / 180 = 1.00, which looks excellent. Count the hit batters as well and the figure becomes 195 / 180 = 1.083, or 1.08. Those 15 runners are real; WHIP just does not see them.

FanGraphs calls WHIP more of a quick reference statistic than a tool for deep analysis, and suggests on-base percentage allowed as a more precise measure of baserunners, because it divides by batters faced. The on-base formula works exactly as it does for hitters; our guide to OPS in baseball walks through it, and the same calculation run against a pitcher becomes OBP against.

WHIP quick reference

A checklist for working out or reading any WHIP:

• Formula: (walks + hits) / innings pitched
• Convert innings first: .1 = one third, .2 = two thirds, never tenths
• No-decimal version: (walks + hits) x 3 / outs
• Lower is better; about 1.30 is roughly average on the FanGraphs rule-of-thumb chart, 1.10 is great and 1.00 is excellent
• Not counted: hit batters, errors, fielder's choice
• Leaderboard qualifier: 1.0 inning pitched per scheduled game
• Read it next to ERA, which counts the runs those baserunners produce