# NORMINV

The **NORMINV** function calculates the inverse of the normal cumulative distribution for a specified mean and standard deviation. It allows you to work backward from a given probability to find the corresponding value on the normal distribution curve.

### Syntax

```javascript
NORMINV(probability, mean, std_dev)
```

### Arguments

The **NORMINV** function syntax has the following arguments:

* probability - A probability corresponding to the normal distribution. Required.
* [mean](/formula-syntax/math-functions/average.md) - The arithmetic mean of the distribution. Required.
* [std\_dev](/formula-syntax/statistical-functions/stdevs.md) - The standard deviation of the distribution. Required.

### Example

<pre class="language-javascript"><code class="lang-javascript"><strong>NORMINV(0.90, 50, 5)
</strong>// Returns 56.41
</code></pre>

You can use the **NORMINV** function to determine critical values or thresholds, such as calculating the specific score required to be in the top 10% of a dataset or finding the target level needed to meet a certain probability.

<figure><img src="/files/zTh0IMcWiRskjgNEgSCY" alt=""><figcaption><p>NORMINV function</p></figcaption></figure>

### Excel Equivalent

[NORMINV](https://support.microsoft.com/en-us/office/norminv-function-87981ab8-2de0-4cb0-b1aa-e21d4cb879b8)

### FAQs

**Q1. What is the relationship between NORMDIST and NORMINV?**

* NORMINV is the mathematical inverse of NORMDIST (when cumulative is set to TRUE).&#x20;
* While [NORMDIST](/formula-syntax/statistical-functions/normdist.md) tells you the probability of a value occurring, NORMINV tells you what the value is for a specific target probability.


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