The On-Base Percentage is calculated by adding up all of the bases a player gets and dividing that by the number of at-bats they had. It’s a measure of how often a hitter gets on base, which is crucial to scoring runs in baseball.

What is On Base Percentage?

On Base Percentage (OBP) is a measure of a player’s ability to reach base safely. It is calculated by adding a player’s hits, walks, and hit-by-pitches, and dividing that total by their at-bats, walks, hit-by-pitches, and sacrifice flies. OBP is expressed as a decimal with three decimal places, such as .354.

Why is On Base Percentage Important?

While traditional baseball statistics such as batting average and home runs provide a good snapshot of a player’s offensive output, they don’t tell the whole story. On Base Percentage takes into account not only hits, but also walks, hit-by-pitches, and sacrifices, which can be just as valuable to a team’s success. Additionally, OBP has been shown to be a better predictor of future performance than batting average or slugging percentage, making it a valuable tool in player evaluation and scouting.

How to Calculate On Base Percentage by Hand

Calculating OBP by hand is relatively simple. Here’s how:

  1. Add the player’s hits, walks, and hit-by-pitches together to get the total number of times they reached base safely.
  2. Divide that total by the sum of the player’s at-bats, walks, hit-by-pitches, and sacrifice flies.Multiply the result by 100 to convert it to a percentage.
  3. Round the result to three decimal places.

Here’s an example:

  • A player has 120 hits, 50 walks, and 10 hit-by-pitches in 500 at-bats, with 5 sacrifice flies.
  • Add the hits, walks, and hit-by-pitches: 120 + 50 + 10 = 180
  • Divide by the sum of at-bats, walks, hit-by-pitches, and sacrifice flies: 180 / (500 + 50 + 10 + 5) = 0.339
  • Multiply by 100: 0.339 * 100 = 33.9%
  • Round to three decimal places: 33.9%

How to calculate the on-base percentage?

The formula for calculating OBP is relatively simple:

OBP = (Hits + Walks + Hit-by-Pitches) / (At Bats + Walks + Hit-by-Pitches + Sacrifice Flies)


  • Hits = the total number of hits a batter has
  • Walks = the total number of walks a batter has received
  • Hit-by-Pitches = the total number of times a batter has been hit by a pitch
  • At Bats = the total number of official at-bats a batter has had (excluding walks and sacrifice hits)
  • Sacrifice Flies = the total number of sacrifice flies a batter has hit

Example Calculation

Let’s say a batter has 100 official at-bats, 25 hits, 20 walks, 5 hit-by-pitches, and 2 sacrifice flies. We can plug these numbers into the OBP formula:

OBP = (25 + 20 + 5) / (100 + 20 + 5 + 2) = 0.429

So this batter has an OBP of .429, which is considered very good in baseball.

How to interpret the result?

The on-base percentage is a measure of how well a batter gets on base. It is calculated by dividing the sum of hits, walks, and hit by pitches divided by his at-bats.

What is OPS – on-base plus slugging?

OPS (On-base plus slugging) is a sabermetric baseball statistic that combines a player’s on-base percentage (OBP) and slugging percentage (SLG) to provide a better measure of a player’s overall offensive performance. It’s calculated by adding a player’s OBP and SLG together.


In essence, OPS measures the player’s ability to get on base and hit for power. A high OPS indicates a strong offensive player, while a low OPS indicates a weaker offensive player. Like OBP, OPS is expressed as a decimal, and a good OPS is generally considered to be above .800.

OPS was first introduced by Branch Rickey, an executive in Major League Baseball, and has gained popularity among baseball analysts and fans. It provides a more complete picture of a player’s offensive production than just looking at OBP or SLG alone.

OPS can be used to compare the offensive abilities of players across different positions and eras, as it accounts for both getting on base and hitting for power. However, like any statistic, it has its limitations and should be used in conjunction with other metrics and scouting observations to evaluate a player’s overall performance.

Examples of On Base Percentage

Let’s look at some examples of OBP to see how it can be used to evaluate a player’s performance. For these examples, we’ll use data from the 2022 MLB season.

Example: Mike Trout

Mike Trout is one of the best players in baseball and consistently ranks among the league leaders in OBP. Here’s how his OBP was calculated in the 2022 season:

  • Hits: 141
  • Walks: 101
  • Hit-by-pitches: 7
  • At-bats: 439
  • Sacrifice flies: 2

Adding his hits, walks, and hit-by-pitches together gives a total of 249. Dividing by the sum of his at-bats, walks, hit-by-pitches, and sacrifice flies gives:

249 / (439 + 101 + 7 + 2) = 0.465

Multiplying by 100 and rounding to three decimal places gives an OBP of 0.465.


What is a good base percentage?

340 OBP is solid, a 360 is very good and significantly higher. 360 is great, with an on-base percentage of. 400 or higher is generally exceptional.

Who has the best on-base percentage in baseball?

Left fielder Ted Williams, who played 19 seasons for the Boston Red Sox, has the highest career on-base percentage, .4817, in MLB history.

What is the best hitting stat?

Since the beginning of baseball, one stat has reigned supreme over all others: the batting average. Simply put, the best hitters are always considered to be those who possess the highest.