# F.INV.RT function

Returns the inverse of the (right-tailed) F probability distribution. If p = F.DIST.RT(x,...), then F.INV.RT(p,...) = x.

The F distribution can be used in an F-test that compares the degree of variability in two data sets. For example, you can analyze income distributions in the United States and Canada to determine whether the two countries have a similar degree of income diversity.

## Syntax

`F.INV.RT(probability,deg_freedom1,deg_freedom2)`

The F.INV.RT function syntax has the following arguments (argument: A value that provides information to an action, an event, a method, a property, a function, or a procedure.):

• Probability     Required. A probability associated with the F cumulative distribution.
• Deg_freedom1     Required. The numerator degrees of freedom.
• Deg_freedom2     Required. The denominator degrees of freedom.

## Remarks

• If any argument is nonnumeric, F.INV.RT returns the #VALUE! error value.
• If probability < 0 or probability > 1, F.INV.RT returns the #NUM! error value.
• If deg_freedom1 or deg_freedom2 is not an integer, it is truncated.
• If deg_freedom1 < 1, or deg_freedom2 < 1, F.INV.RT returns the #NUM! error value.
• If deg_freedom2 < 1 or deg_freedom2 ≥ 10^10, F.INV.RT returns the #NUM! error value.

F.INV.RT can be used to return critical values from the F distribution. For example, the output of an ANOVA calculation often includes data for the F statistic, F probability, and F critical value at the 0.05 significance level. To return the critical value of F, use the significance level as the probability argument to F.INV.RT.

Given a value for probability, F.INV.RT seeks that value x such that F.DIST.RT(x, deg_freedom1, deg_freedom2) = probability. Thus, precision of F.INV.RT depends on precision of F.DIST.RT. F.INV.RT uses an iterative search technique. If the search has not converged after 64 iterations, the function returns the #N/A error value.

## Example

The example may be easier to understand if you copy it to a blank worksheet.

1. Select the example in this article. If you are copying the example in Excel Online, copy and paste one cell at a time.
Important: Do not select the row or column headers.

Selecting an example from Help

1. Press CTRL+C.
2. Create a blank workbook or worksheet.
3. In the worksheet, select cell A1, and press CTRL+V. If you are working in Excel Online, repeat copying and pasting for each cell in the example.
Important: For the example to work properly, you must paste it into cell A1 of the worksheet.
4. To switch between viewing the results and viewing the formulas that return the results, press CTRL+` (grave accent), or on the Formulas tab, in the Formula Auditing group, click the Show Formulas button.

After you copy the example to a blank worksheet, you can adapt it to suit your needs.

A B
Data Description
0.01 Probability associated with the F cumulative distribution
6 Numerator degrees of freedom
4 Denominator degrees of freedom
Formula Description (Result)
=F.INV.RT(A2,A3,A4) Inverse of the F probability distribution for the terms above (15.20686486)

Applies to:
Excel 2010, Excel Web App, SharePoint Online for enterprises, SharePoint Online for professionals and small businesses