Add a trendline by selecting your chart, opening the chart editor, and choosing the trendline option

A trendline is a line that runs through your data points to show the overall direction or pattern. In Google Sheets, you add one through the chart editor in about three clicks. The trendline helps you see whether your data is going up, down, or staying flat — useful when the individual data points are scattered or hard to read at a glance.

The process works the same way whether your chart is a line chart, scatter plot, column chart, or bar chart. You do not need to install anything or write a formula. Google Sheets builds the trendline for you once you tell it which data series to apply it to.

Key Takeaways

  • Double-click your chart to open the chart editor, then click the Series tab and select the data series you want the trendline on.
  • Scroll down in the Series panel to find Trendline, check the box, and choose Linear, Exponential, Polynomial, or Power from the dropdown.
  • Linear trendlines work for most everyday data; use Exponential or Polynomial only if your data clearly curves rather than following a straight pattern.
  • You can add a trendline to one data series or multiple series on the same chart, and customize the line color and style in the Format tab.

Step-by-step: Adding a trendline to your chart

Start by clicking on the chart itself. A border appears around it. Double-click the chart to open the chart editor panel on the right side of your screen.

In the chart editor, click the Series tab (the second tab from the left). You will see a list of your data series — usually labeled by the column header you used. Click the series name you want to add a trendline to.

Scroll down in the Series panel until you see the Trendline section. Check the box next to Trendline. A dropdown menu appears with four options: Linear, Exponential, Polynomial, and Power. Select Linear unless you have a reason to choose something else.

The trendline appears on your chart immediately. You can close the chart editor by clicking outside the chart, or keep it open to adjust colors or other settings.

When to use each trendline type

Linear is the default and the right choice for most data. Use it when your data points seem to follow a roughly straight path — either climbing, falling, or staying level. Sales over time, temperature changes, or test scores across a group usually work well with linear trendlines.

Exponential trendlines curve upward or downward and work when your data grows or shrinks faster and faster. Viral spread, compound interest, or bacterial growth often follow exponential patterns. If your data points cluster near the bottom left and shoot up toward the top right, exponential may fit better than linear.

Polynomial trendlines bend and curve to follow more complex patterns. They are useful when your data rises, peaks, then falls — like sales through a product lifecycle or temperature through a day. Polynomial trendlines can fit the data more closely than linear ones, but they can also overfit and show patterns that are not really there.

Power trendlines follow a power law relationship and are less common in everyday use. They work for data where one variable is proportional to another raised to a power — for example, the relationship between a circle's radius and its area.

Customize the trendline color and style

After you add a trendline, you can change how it looks. With the chart editor still open, click the Format tab (the third tab from the left).

In the Format tab, click Series in the left menu, then scroll down to find Trendline. You can change the line color by clicking the color box, adjust the line thickness with the slider, and choose a solid or dashed line style from the dropdown.

These changes are purely visual and do not affect how the trendline is calculated. Make the trendline stand out by using a contrasting color — for example, a bright red trendline over blue data points — so viewers can see the trend clearly.

Add multiple trendlines to the same chart

If your chart has more than one data series, you can add a trendline to each one. In the Series tab of the chart editor, click the first series, scroll down, and check Trendline. Then click the second series and do the same.

Each trendline calculates independently based on its own data series. This is useful when you are comparing trends across groups — for example, sales trends for Product A and Product B on the same chart. Use different colors for each trendline so they do not blend together.

Be careful not to add too many trendlines to one chart. More than three or four trendlines can make the chart hard to read. If you need to show many trends, consider splitting them into separate charts instead.

What the trendline equation and R-squared value mean

Google Sheets can display the trendline equation and R-squared value directly on your chart. These are optional but useful if you want to understand the math behind the trend.

To show them, open the chart editor, go to the Series tab, select your series, scroll to Trendline, and check the boxes for Show equation and Show R² value. The equation appears as text on the chart — for a linear trendline, it looks like y = 2.5x + 10, which means your data increases by 2.5 units for every unit increase in x.

The R² value (pronounced "R-squared") tells you how well the trendline fits your actual data. It ranges from 0 to 1. A value of 1 means the trendline matches your data perfectly. A value of 0.8 or higher usually means the trendline is a good fit. A value below 0.6 means the trendline does not capture your data well, and you may want to try a different trendline type or check whether your data has outliers throwing off the trend.

Troubleshooting trendline problems

If the Trendline option is grayed out or missing, check that your chart type supports trendlines. Scatter plots, line charts, column charts, bar charts, and area charts all work. Pie charts, donut charts, and gauge charts do not support trendlines.

If your trendline looks wrong or does not match your data, you may have selected the wrong trendline type. Try switching from Linear to Polynomial or Exponential to see if the fit improves. You can also check the R² value — if it is very low, the trendline type you chose may not be right for your data.

If you added a trendline but cannot see it on the chart, it may be hidden behind your data points or colored the same as the background. Open the Format tab, click Series, scroll to Trendline, and change the line color to something bright and visible.

Frequently Asked Questions

Can I remove a trendline after I add it?

Yes. Open the chart editor, go to the Series tab, select the series with the trendline, scroll to Trendline, and uncheck the box. The trendline disappears immediately. You can add it back the same way if you change your mind.

Does the trendline change if I update my data?

Yes. Google Sheets recalculates the trendline automatically whenever you change the data in your chart. If you add new rows or edit existing values, the trendline updates to match the new data.

What is the difference between a trendline and a moving average?

A trendline is a single line that represents the overall direction of your data. A moving average smooths out short-term ups and downs by averaging groups of nearby data points. Google Sheets calls moving averages "Moving Average" in the Trendline dropdown. Use a trendline to show the big-picture trend; use a moving average to smooth out noise while keeping the line closer to your actual data.

Can I export or copy the trendline equation?

You can see the equation on the chart if you check "Show equation" in the Series tab. To use the equation in a formula elsewhere in your sheet, you would need to type it manually or use Google Sheets' FORECAST or TREND functions instead. The trendline itself is part of the chart and cannot be extracted as a separate object.