Baseball Isolated Power (ISO)

baseball isolated power iso

In baseball, a common way of measuring a hitter’s power is through a statistic called isolated power, or ISO. How does ISO work? How is it calculated? What is its purpose? Read on to find out.

Isolated Power (ISO)

Isolated power is a statistic which measures a hitter’s raw power. It considers only extra-base hits, and emphasizes the different types of extra-base hits differently. Triples receive twice the weight of doubles in ISO calculations and home runs are worth three times as much. By focusing only on extra-base hits and their type, ISO shows a batter’s ability to achieve the location and distance necessary to hit for extra bases.

ISO Formula

The formula for ISO is:

(Doubles + 2 x Triples + 3 x Home runs) / At-bats = ISO


Slugging percentage - Batting average = ISO


For example, a player who goes 1-for-5 with a double would have an ISO of .200. Another player who goes 2-for-5 with a single and a double would have the same .200 ISO but also a higher batting average than the first player.


What is ISO in baseball?

In baseball, ISO evaluates a hitter’s raw power by counting the number and type of extra-base hits they get per at bat. Triples are weighed at twice the rate of doubles, and home runs count for three times as much. Singles are not counted.