A sabermetrics statistic created by Banch Rickey and Allan Roth in the 1950s that measures a hitters ability to hit. More specifically it's the batter's ability to hit for extra bases, it is sometimes referred to as 'Power Average' or 'Raw Power'.
The calculation for Isolated Power (ISO) is:
ISO = ((2B) + (2*3B) + (3*HR)) / AB
In the simplest form, isolated power is attained by subtracting batting average from slugging percentage (ie. SLG of .500 and AVG of .300 you are left with an ISO of 0.200).
The range for ISO is 0 to 3,000. An ISO of 0 means that a player only hits singles, and an ISO of 3,000 is only possible if a player just hits home runs and nothing else. Below are the general ranges for ISO rating:
|Excellent||0.250 or higher|
Isolated power is a very useful baseball statistic that makes up the foundation of sabermetrics. The one caveat of ISO is that the calculation requires a larger sample size of at bats to be considered accurate and reliable for future predictions. Ideally at least 500 plate appearances (some say minimum 1,000 at bats) before considering a player's ISO to be accurate.