Expected Fielding Independent Pitching or xFIP, like FIP, also measures what a player’s ERA should have looked like compared to what it actually is, but does so using the league average home run rate (10.6% HR/FB).
Although home runs are not as random as balls in play that involve defense, it has been discovered that a pitcher’s home run rate often varies from year to year. xFIP eliminates the variance.
Formula: (13*(.11*fly balls) + 3*(BB+HBP-IBB) – 2*K)/IP + constant (2011 constant is 3.12)
xFIP Calculator
