The Excel FINV Function

FINV and F.INV.RT

In Excel 2010, the Finv function has been replaced by the F.Inv.Rt function, which has improved accuracy.

Although it has been replaced, the Finv function is still available in Excel 2010 (stored in the list of compatibility functions), to allow compatibility with earlier versions of Excel.

However, the Finv function may not be available in future versions of Excel, so it is advised that you use the F.Inv.Rt function, if possible.

Related Function:
FDIST Function

Function Description

The Excel FINV function calculates the inverse of the (right-tailed) F Probability Distribution for a supplied probability.

The syntax of the function is:

FINV( probability, deg_freedom1, deg_freedom2 )

Where the function arguments are:

probability-The probability (between 0 and 1) at which to evaluate the inverse F Probability Distribution.
deg_freedom1-An integer specifying the numerator degrees of freedom.
deg_freedom2-An integer specifying the denominator degrees of freedom.

If either deg_freedom1 or deg_freedom2 are decimal numbers, these are truncated to integers by Excel.

Note that the Excel Finv function is the inverse of the Excel FDIST function.

I.e. if
FDIST( x, deg_freedom1, deg_freedom2 ) = probability
then
FINV( probability, deg_freedom1, deg_freedom2 ) = x

Finv Function Example

Plot of the Inverse F Probability Distribution with numerator degrees of freedom = 1 and denominator degrees of freedom = 2
Inverse F Prob. Dist. with deg_freedom1 = 1 & deg_freedom2 = 2

The above chart on the right shows the inverse of the right-tailed F Probability Distribution with the numerator degrees of freedom equal to 1 and the denominator degrees of freedom equal to 2.

If you want to calculate the value of this function for a probability equal to 0.2, this can be done using the Finv function, as follows:

=FINV( 0.2, 1, 2 )

This gives the result 3.555555556.


For further details and examples of the Excel Finv function, see the Microsoft Office website.


Finv Function Errors

If you get an error from the Excel Finv function this is likely to be one of the following:

Common Errors
#NUM!-

Occurs if either:

  • The supplied probability is ≤ 0 or > 1
or
  • The supplied deg_freedom1 or deg_freedom2 is < 1 or ≥ 10^10.
#VALUE!-Occurs if any of the supplied arguments is non-numeric.