Confidence intervals of sample means help measure the mean of a population. They’re easy to calculate with a spreadsheet. Let’s learn **how to find confidence intervals in Microsoft Excel.**

## How to Find Confidence Intervals in Excel

For a mean, there are two confidence intervals: **lower** and **upper.** These form a range around your mean, and have a percentage likelihood. A **90%** interval, for example, suggests that 90 of 100 intervals sampled will contain the mean value.

Consider a dataset where you need to find the confidence interval. To begin, navigate to the **Data** tab on Excel’s ribbon. On the far right side, click on the **Data Analysis** button. You’ll see the **Data Analysis** popup menu, which contains a long list of** Analysis Tools.**

To find the confidence intervals, you’ll want to select **Descriptive Statistics.** Choose this option from the list, then click **OK.**

You’re now on the **Descriptive Statistics** menu. Here, you’re given a few choices for your data. First, click into the **Input Range** box. Then, click and drag to highlight the relevant data on your spreadsheet. In this case, that’s cells **A2:A6.**

Since this data is in a column, leave the **Columns** button selected. To include your labels, click **Labels** to incorporate the headers. Check the **Summary Statistics** box.

Finally, **Confidence Level for Mean** asks you to specify your desired confidence interval. It defaults to **95%,** which is commonly used in statistics.

When you’re finished, click **OK. **You’ll see a data report on a new worksheet. At the bottom is your confidence interval. To find your upper confidence interval, add cell** B16** to cell **B3** (your mean). To find the lower confidence interval, subtract cell **B16** from cell **B3. **

As you can see, Excel takes the hard work out of finding confidence intervals for sample data. This is a useful statistical analysis that you can perform over and over again.