Sometimes, we need to determine the value of the **Z score** at different levels of confidence, according to our desire. In this article, we will demonstrate to you the step-by-step procedure to calculate the **Z** score with a **95** confidence interval in Excel. If you are also curious about it, download our practice workbook and follow us.

## Download Practice Workbook

Download this practice workbook for practice while you are reading this article.

## What Is Z Score?

**Z Score** is a special type of value that indicates how far the value is from the mean. The general formula for **Z score** is:

Here,

**Z**represents the value of the**Z score****X**is the value of any case**μ**stands for the**mean**value**σ**represents the value of the**Standard Deviation**

## What Is Confidence Interval?

In statistics, a **confidence interval** describes the likelihood that a dataset parameter will fall between a set of values for a predetermined percentage of the time. Analysts frequently employ **confidence intervals** that include **95%** or **99%** of anticipated observations.

## How to Calculate Z Score with Conventional Method

Here, we will show the manual calculation process of the **Z score.** The steps of this manual process are given below:

**📌 Steps:**

- First, choose a dataset. Here, we use a simple dataset with
**5**data. Those**5**values are**82**,**77**,**85**,**78**, and**80**. - Second, we will estimate the simple
**Mean**of this dataset.

- Third, we have to evaluate the
**Standard Deviation**of our data. - You can see that the value of the
**Standard Deviation**is**2.87**. So, the dataset is**normally distributed**.

- Choose your desired confidence level interval. For our data, we set it at
**95%**. - After that, in the
**Z-Score chart**, we have to find out the value of**0.975**(e.g.**0.95+(0.05/2)=0.975**). - Now, you may notice that the
**vertical axis**value for**0.975**is**1.9**and the**horizontal axis**value is**0.06**.

- Thus, our
**Z-score**value for a**95%**confidence interval will be**1.9+0.06****= 1.96**.

So, we can say that we are able to estimate the **Z score** with a **95** confidence interval manually.

## Step-by-Step Procedure to Calculate Z-Score with 95 Confidence Interval in Excel

In this section, we are going to show you the step-by-step procedure to evaluate the **Z-score** value with a **95** confidence interval in Excel.

### Step 1: Calculate Mean of Dataset

In this first step, we will calculate the **Mean** value of our total marks number. For that, we are going to use **the AVERAGE function**.

- At first, select cell
**F5**. - Now, write down the following formula into the cell.

`=AVERAGE(C5:C14)`

- Press
**Enter**.

- You will get the value of the mean of our dataset.

Thus, we can say that we have completed the first step, to calculate the **Z score** with a **95** confidence interval in Excel.

**Read More:** **Excel Confidence Interval for Difference in Means (2 Examples)**

### Step 2: Estimate Standard Deviation

Now, we are going to estimate the **Standard Deviation** of our dataset. To determine the value, we will use **the STDEV.P function**.

- First, select cell
**F6**. - After that, write down the following formula into the cell.

`=STDEV.P(C5:C14)`

- Press the
**Enter**key.

- You will get the value of the
**Standard Deviation**. - Now, you may notice that the value of the
**Standard Deviation**is**2.914**. So, we can take the decision that our dataset is**normally****distributed**.

So, we can say that we have finished the second step, calculating the **Z score** with a **95** confidence interval in Excel.

**Read More:** **How to Calculate 90 Percent Confidence Interval in Excel**

### Step 3: Define Confidence Interval Level

In this step, we have to define our confidence level interval.

- At first, title cells
**E7**and**E8**as**Confidence level**and**Alpha**, respectively.

- Now, in cell
**F7**, define the**confidence interval****level**. Here, we define our**confidence interval which is 95%**

- After that, in cell
**F8**, write down the following formula to get the Alpha value.

`=1-F7`

- Then, press
**Enter**.

- Our task is completed.

Therefore, we can say that we have accomplished the third step, calculating the **Z score** with a **95** confidence interval in Excel.

### Step 4: Estimate Z Score for Desired Confidence Interval

In this final step, we will estimate the **Z score** value for our desired confidence interval level. To determine the value of the **Z score**, we will use the **NORM.S.INV** and **ABS** functions.

- Firstly, select cell
**F10**. - Now, write down the following formula into the cell.

`=ABS(NORM.S.INV((F8)/2))`

- Press
**Enter**.

- You will get the
**Z score**value with a**95**confidence interval level which is equal to the manual procedure.

Finally, we can say that we have finished the final step, calculating the **Z score** with a **95** confidence interval in Excel.

**🔎**** Breakdown of the Formula**

We are breaking down the formula for cell **F10**.

`👉`

**NORM.S.INV((F8)/2)**: The **NORM.S.INV** function provides us the **Z-score** value of **0.025**. As this interval level is at the right side of the mean position, the value will show a negative sign. Here, the function returns **-1.960**.

`👉`

**ABS(NORM.S.INV((F8)/2))**: The **ABS** function will show the absolute value of the result of the **NORM.S.INV** function. For this cell, the function returns **1.960**.

**Read More:** **How to Calculate P-Value from Confidence Interval in Excel**

## Conclusion

That’s the end of this article. I hope that this article will be helpful for you and you will be able to calculate z-score 95 confidence interval in Excel. Please share any further queries or recommendations with us in the comments section below if you have any further questions or recommendations.

Don’t forget to check our website, **ExcelDemy**, for several Excel-related problems and solutions. Keep learning new methods and keep growing!