The invnorm calculator determines the opposite normal probability distribution by sketching their graph. This calculator also evaluates the confidence interval along with their two tails and left-right values based on the probability, mean, and __standard deviation__.

## What is Invnorm?

Invnorm is the short form of inverse normal distribution. It is defined as;

**“**It is the method of using the known probabilities in order to determine the reciprocal of a random variable and the z critical value in the normal distribution.**”**

It has a bell-shaped curve graph that illustrates the technique of working to find the x-value

## Invnorm Formula:

For a given area below a certain value, the invnorm is used for calculating a known probability to determine the corresponding z-critical value in a normal distribution.

By the below invnorm formula, you can find the inverse of normal distribution.

$$ f(x)=\frac{1}{\sqrt{2\pi\sigma^2}}e^{-\displaystyle{\frac{(x-\mu)^2}{2\sigma^2}}} $$

**Where:**

- μ _ Arithmetic mean of the distribution
- σ _
__variance__that measures the dispersion - e _ Exponential functions
- x _ Independent variable

## Steps To Use The Calculator?

The inverse normal distribution calculator works by taking some inputs into account. So, look at these points:

### What To Do?

- Insert the value of the
__probability__ - Enter the mean and standard deviation
- Tap
**“Calculate”**

### What You Get?

- Left, Right, and two tail values
- Standard Deviation with the graph indication

## References:

**Wikipedia:** Inverse distribution, Relation to original distribution, Examples.