Error bars show the range of uncertainty around your data
Error bars are lines extending above and below each data point on a chart, showing how much that measurement might vary. In Google Sheets, you add them through the chart editor by selecting your data series and choosing an error bar type. The bars can represent standard deviation, standard error, percentage, or a fixed value you enter yourself.
Error bars are useful when you're presenting measurements that have some built-in uncertainty — test scores with a margin of error, scientific measurements with known variation, or averages calculated from samples. They tell viewers at a glance that your numbers are not exact, and how much confidence to place in them.
Key Takeaways
- Error bars are added through the chart editor, not by editing the spreadsheet data itself.
- You choose the error bar type based on what your data represents: standard deviation for variation within a dataset, standard error for sample averages, or a percentage or fixed value for other situations.
- Google Sheets can calculate error bars automatically from your data, or you can specify a fixed amount if you already know the margin of error.
- Error bars only work on scatter, column, bar, and line charts — not on pie charts or other chart types.
Create or open a chart with your data
Start with a spreadsheet that has your data already entered. You need at least two columns: one for your categories or x-axis values, and one for the measurements you want to show. If you're using a scatter chart, you'll have an x column and a y column.
Select the data range including headers, then go to Insert and click Chart. Google Sheets will create a default chart. If you already have a chart, double-click it to open the chart editor.
Open the chart editor and find the error bar settings
Once the chart editor is open on the right side of your screen, click the Series tab. You'll see a list of the data series in your chart — usually just one, labeled with the column header from your spreadsheet.
Click on the series name to select it. Below the series list, you'll see options for that series. Scroll down until you find Error bars. Click the checkbox next to it to turn error bars on.
Choose what your error bars represent
Once you check the error bars box, a dropdown menu appears asking you to choose the error bar type. The most common options are:
- Standard deviation: Shows how spread out your individual data points are. Use this when each point in your chart is a single measurement from a larger group, and you want to show the typical variation within that group.
- Standard error: Shows the uncertainty in an average or mean. Use this when each point represents an average of multiple measurements, and you want to show how confident you are in that average.
- Percentage: Extends the bars by a percentage of each data value. Use this when your margin of error scales with the size of the measurement — for example, if larger numbers are naturally less precise.
- Fixed value: Extends the bars by the same amount above and below every point. Use this when you know a specific margin of error that applies to all measurements equally.
If you choose percentage or fixed value, an additional field appears where you enter the number. For percentage, enter just the number (for example, 10 for 10 percent). For fixed value, enter the amount in the same units as your data.
Customize the appearance of your error bars
After selecting the error bar type, you can adjust how they look. In the same Series tab, you'll find options for Color and sometimes Line width. Change the color to make the bars stand out or match your chart's design. A thicker line width makes the bars more visible on a crowded chart.
You can also adjust the overall chart appearance by clicking the Customize tab in the chart editor. Here you can change the chart title, axis labels, legend position, and other visual elements that work alongside your error bars.
explore the chart and check your work
Once your error bars are set up the way you want them, click Insert at the bottom of the chart editor to place the chart in your spreadsheet. If you're editing an existing chart, the changes explore automatically when you close the editor.
Look at the chart and verify that the error bars make sense. They should extend symmetrically above and below each point (or to the right and left for horizontal bar charts). If the bars look too large or too small, go back into the chart editor, click the series again, and adjust the error bar type or value.
Common mistakes and how to fix them
The most common problem is choosing the wrong error bar type. If you selected standard deviation but your data is already averaged, the bars will be too large. Switch to standard error instead. If you're using a fixed value and the bars don't look right, double-check that you entered the number in the correct units.
Another issue is that error bars don't appear on certain chart types. Google Sheets only supports error bars on scatter, column, bar, and line charts. If you're using a pie chart, area chart, or combo chart, the error bar option won't be available — you'll need to switch to one of the supported types.
If your error bars are barely visible, try increasing the line width in the Series tab, or changing the color to something that contrasts with the chart background. Very small error bars can disappear against the chart gridlines.
Frequently Asked Questions
Can I use different error bar values for different data points?
No, Google Sheets applies the same error bar calculation to all points in a series. If you need different margins of error for different points, you would need to create separate data series for each group and assign different error bar values to each series.
What's the difference between standard deviation and standard error?
Standard deviation shows how spread out individual measurements are within a single group. Standard error shows how confident you are in an average when that average comes from a sample. If each point on your chart is an average of multiple measurements, use standard error. If each point is a single measurement from a larger population, use standard deviation.
Why don't my error bars show up on my chart?
Error bars only work on scatter, column, bar, and line charts. If you're using a pie, area, or combo chart, switch to one of the supported types. Also check that you actually clicked the checkbox to turn error bars on — it's straightforward to miss in the Series tab.
Can I add error bars to only some of the data series in a multi-series chart?
Yes. In the Series tab, click on one series name, turn on error bars for it, then click a different series name and leave error bars off. Each series can have its own error bar settings or none at all.