The Excel BETA.INV function calculates the inverse of the cumulative beta probability density function for a supplied probability. The Beta.Inv function is new to Excel 2010 and so is not available in earlier versions of Excel. However, the function is simply an updated version of the Betainv function, which __is__ available in earlier versions of Excel.

**Syntax**:= BETA.INV(probability,alpha,beta,[A],[B])

The BETA.INV function syntax has the following arguments:

**Probability**Required. A probability associated with the beta distribution.**Alpha**Required. A parameter of the distribution.**Beta**Required. A parameter the distribution.**A**Optional. A lower bound to the interval of x.-
**B**Optional. An upper bound to the interval of x.

**Example**: Let’s look at some Excel BETA.INV function examples and explore how to use the BETA.INV function as a worksheet function in Microsoft Excel:

**Example 1**:

**Syntax**: =BETA.INV(B1,B2,B3,B4,B5)

**Result**: 1.776506506

**Example 2**:

Beta Inverse function – BETA.INV, is supplied values from 0.1 to 0.9 on interval of 0.1 along with alpha value as 8, beta value as 9, [A] as 0 and [B] as 1

So the result will be

Inverse Cumulative Beta Distribution, calculated for alpha=8 and beta=9 by the BETA.INV function is shown in above table and the same is plotted below**.**

**Note**:

- If any argument is non numeric, BETA.INV returns the #VALUE! error value.
- If alpha ≤ 0 or beta ≤ 0, BETA.INV returns the #NUM! error value.
- If probability ≤ 0 or probability > 1, BETA.INV returns the #NUM! error value.
- If you omit values for A and B, BETA.INV uses the standard cumulative beta distribution, so that A = 0 and B = 1.
- Given a value for probability, BETA.INV seeks that value x such that BETA.DIST(x, alpha, beta, A, B) = probability. Thus, the precision of BETA.INV depends on the precision of BETA.DIST.