In this tutorial, I will discuss 4 suitable methods to find the x-intercept in Excel.

**Table of Contents**Expand

## What Is x-Intercept?

If a straight line intersects X-axis at (2,0), the x-intercept will be 2. So, you can say that the x-intercept is the x-ordinate of a point on a straight line, where the line intersects the X-axis.

## How to Find X Intercept for Linear Data in Excel

We will consider a linear equation (**y = 3x â€“ 7**). To be specific, it is a straight-line equation. Here, we will find a value of **X** when **y = 0**.

First, choose cell **C12** >> apply the following formula >> hit **Enter.**

`=INTERCEPT(B6:B10,C6:C10)`

Now, plot a **Scatter with Smooth Lines and Markers** chart to get a better understanding.

**Important Notes**

- The
**INTERCEPT**function finds the point at which a line intersects the y-axis. It uses known x-values and known y-values.

- Note that, the
**INTERCEPT**function considers the intersection at the y-axis which means it calculates the y-intercept. - So, when you calculate the x-intercept with the
**INTERCEPT**function, your y-values will be**INTERCEPT**â€™s x values and your x-values will be**INTERCEPT**â€™s y-values.

## How to Find x-Intercept in Excel: 5 Suitable Methods

Letâ€™s consider the following data consists of **monthly Covid cases** (set as Y-values) and **monthly use of masks** (set as X-values).

We have to know *which percentage of people are still using masks when the number of covid cases becomes zero*. Excel has many functions and features to find the x-intercept. Of them, we will see 4 in the next sections.

**1. Using INTERCEPT Function to Find x-Intercept**

If you just need to know the x-intercept, then using the **INTERCEPT function** of Excel is the fastest method.

**ðŸ”€ Steps:**

- Use the following formula in
**Cell C18**to find the x-intercept of this Covid-Mask data.

`=INTERCEPT(C5:C16,D5:D16)`

- Here,
**your x-values**=**C5:C16**â‡’**y-values in the formula**. - And
**your y-values**=**D5:D16**â‡’**x-values in the formula**. - So, we get the
**x-intercept = 90.16%**(*after applying the percentage format of Excel*).

**ðŸ”Ž**** Interpretation of x-Intercept:**

- x-Intercept means the y value is set to zero. In our case, the y-value is covid cases.
- So, this result means: when the use of masks is 90.16%, the covid cases will be zero.
- Or, when the covid cases tend to zero, the use of masks among people is still 90.16%.

### 2. Using FORECAST.LINEAR Function to Find X-Intercept

Here, we will use **FORECAST.LINEAR** to find X Intercept for the above dataset.

**ðŸ”€ Steps:**

- First, choose cell
**D19**>> apply the following formula >> hit**OK.**

`=FORECAST.LINEAR(D18,C5:C16,D5:D16)`

**Notes**

When calculating X Intercept using the **FORECAST.LINEAR** function, we must switch between the **known_ys** and **know_xs** values. So, use People Using Masks (X) as known_ys and Covid Cases (Y) as know_xs.

**3. Using the Trendline Equation Feature of Excel Graph**

You can also find the x-intercept by using the **Trendline Equation feature of the Excel graph** created from the dataset you have. Follow the steps below to do this.

**ðŸ”€ Steps:**

- First, go to the
**Insert tab**and click on the**Scatter icon**and select the first suggested icon.

- A blank graph canvas will appear.
- Now, click on the
**Chart Area****canvas**and then right-click on your mouse. Then click on**Select Dataâ€¦****option**.

- From the
**Select Data Source****window**, press the**Add button**.

- The
**Edit Series pop-up**will appear. - From this window, give a suitable name for the series.

- Then choose
**X values**.*Note that, like the previous method, Excelâ€™s X values are equivalent to our Y values here.*

- Similarly, choose the
**Y values**. - Then, press
**OK**.

- Now we will be back to the
**Select Data Source window**again. - Notice that the
**Calculate x-Intercept**(the name we gave) series appears and is selected automatically. - Finally, press the
**OK****button**.

- You are done with making the graph, a couple more steps to get the result now.
- Click on the
**Chart Elements button**(a**+ sign**you see in the image below). - Then unmark the
**Gridlines**for a better view. - After that, select the
**Trendline****option**and click on the**angle icon**(**âŒª**) just beside it. - Select More Options.

- A window named
**Format Trendline**will appear. - From this window, click the
**3rd icon**(when hovering your mouse, you will see its name is**Trendline Options**). - Then select the
**Linear radio button**. - Lastly, mark the â€˜
**Display****Equation****on the chartâ€™**checkbox.

- Get back to the graph.
- You will see that an equation appears in the chart area.
- The equation is:

**y=-0.0001x+0.9016**

- So, finally, we get the desired result, our x-intercept is
**0.9016**(*90.16%, when formatted as a percentage*).

**Read More:** **How to Set Intercept Trendline in Excel**

**4. Using LINEST Function to Find x-Intercept**

The **LINEST function** is another option to find the x-intercept in Excel. This function is a combination of **SLOPE** and **INTERCEPT** functions. It returns slope and intercepts as well with a single click.

**ðŸ”€ Steps:**

- Here is the formula to use the
**LINEST**function to get the x-intercept.

`=LINEST(C5:C16,D5:D16)`

- Put this formula in
**Cell****C19**and press**ENTER**.

- And you will get an intercept in
**Cell****C20**(*and a slope in*).**Cell****C19**

**Read More:** **How to Find Intercept of Two Lines in Excel**

**5. Using Data Analysis ToolPak**

The fourth option is using the **Data Analysis ToolPak of Excel**.

**ðŸ”€ Steps:**

- To enable the
**Data Analysis ToolPak**, press**ALT+F+T**and get to the**Excel****Options****window**. - Then go to the
**Add-ins****section**and select**Excel Add-ins**from the**Manage****drop-down**. - Then click on the
**Go****button**.

- A new window will pop up named
**Add-ins**. - Mark the
**Analysis ToolPak checkbox**and press**OK**.

- Now you will have this feature on your
**Excel****ribbon**. - Go to the
**Data****tab**and click on**Data Analysis**from the**Analysis****group**.

- From the
**Data Analysis options**, select**Regression**and press**OK**.

- The
**Regression****window**will pop up. - Select
**Input Y Range**first, remember that you have to select your X-values here. - Similarly, select
**Input****X****Range**. - Finally, press
**OK**.

- You will be back to the
**Regression****window**again. - Select where to place the
**Output****Range**(*in our case, the location is*).**Cell****F4** - Then press
**OK**.

- The regression summary will be generated by ToolPak.
- From this report, you will get the x-intercept along with other statistics.
- In the following image, we have highlighted the x-intercept.

**Read More:** **How to Find Y Intercept in Excel**

**Quick Notes**

- You must remember that all through the article, we have considered the X values of our data as the known_ys (and vice versa for Y values) of the Excel function or graph tool or the Data Analysis tool.
- Use the
**INTERCEPT**and**Trendline Equation**methods if you just need to know the x-intercept quickly.

**Download Practice Workbook**

Download the following workbook for your practice from the following link.

**Concluding Words**

So thatâ€™s it for today. I hope you have enjoyed this article and can easily find the x-intercept now. If you face any problems, then leave us a comment.Â Thank you!

**<< Go Back toÂ Excel INTERCEPT Function | Excel Functions | Learn Excel**

Hey, these 4 methods to determine an x-intercept for a data set are wrong. You have to determine the x incept for a given line by solving the equation of a line for x and setting y=0. None of these methods provide and even close to accurate value for a data sets linear regression line’s x-intercept. READER BEWARE.

Hello

Dr TimberI went through this article and did not find any technical issues. In my view, you should reconsider what you have said.

This article is about finding an

X intercept. To demonstrate this point, this context considers a practical dataset where the percentage of people still using masks is calculated when the number ofCovid CasesbecomesZero. I think you expected the calculation to findX InterceptforY = 0. That’s what is calculated in those methods. When the writer introduced us to the dataset, it was explicitly mentioned.Anyway, I am introducing another method that may overcome your confusion. I have calculated the percentage of people who still use masks when the number of Covid Cases becomes Zero. I am using

FORECAST.LINEAR Functionto predict the percentage. And I get the same result shown in this article.Excel Formula:The data considered in this article is not Linear. That’s why you get confused. However, these methods must be able to find an X intercept for any Linear data.

Stay safe. And good luck!

Regards

Lutfor Rahman Shimanto