PowerPoint bar charts display data using vertical or horizontal bars. The space between each bar is controlled by a setting called Gap Width. When you want thicker bars or thinner bars, you adjust the Gap Width value. This article explains how Gap Width works and provides the exact steps to change bar width in your chart.
Key Takeaways: Adjusting Bar Width With Gap Width
- Format Data Series > Series Options > Gap Width: The only slider that controls bar thickness and spacing in a PowerPoint bar chart.
- Gap Width range 0% to 500%: Lower values create thicker bars with less space; higher values create thinner bars with more space.
- Click on the bars, not the chart border: You must select the individual data series to see the Gap Width option in the Format pane.
What Gap Width Does in a PowerPoint Bar Chart
Gap Width is the space between bars in a PowerPoint bar chart, measured as a percentage of the bar width. The default setting is 150%. At 150%, the gap between bars is 1.5 times the width of a single bar. When you decrease the Gap Width percentage, the bars become wider and the gaps become narrower. When you increase the percentage, the bars become thinner and the gaps become wider.
Gap Width applies to all bars in one data series. If your chart has multiple series, each series has its own Gap Width setting. Adjusting the Gap Width for one series does not affect the others unless you select each series individually.
No other setting in PowerPoint directly controls bar width. The Gap Width slider is the only tool for this task. There is no separate “bar thickness” option.
Steps to Change Bar Width Using Gap Width
Follow these steps to adjust the bar width in any PowerPoint bar chart.
- Select the chart
Click once on the chart object to activate the Chart Tools tabs in the ribbon. The chart border becomes visible with selection handles. - Click on the bars
Click directly on any bar in the data series you want to adjust. All bars in that series become selected. Do not click the chart border or the plot area. - Open the Format Data Series pane
Right-click the selected bars and choose Format Data Series from the context menu. The Format Data Series pane opens on the right side of the PowerPoint window. - Locate the Gap Width slider
In the Format Data Series pane, select the Series Options tab (the bar chart icon). The Gap Width slider appears under the heading Series Options. - Adjust the Gap Width value
Drag the slider left to decrease the Gap Width percentage and make bars thicker. Drag the slider right to increase the percentage and make bars thinner. The chart updates in real time as you drag. - Set a precise percentage
Click the number box next to the slider and type a value between 0 and 500. Press Enter to apply the exact percentage.
Adjusting Gap Width for Multiple Series
If your chart contains more than one data series, repeat the steps for each series. Click on a bar in the second series, open the Format Data Series pane, and set the Gap Width to the same or a different value.
Common Mistakes When Adjusting Bar Width
Gap Width slider is grayed out or missing
This happens when you select the chart but not the bars. Click directly on a bar to select the data series. The slider becomes active only when a data series is selected.
Bars become too thin or too wide
Gap Width values below 20% produce very thick bars with almost no gap. Values above 400% produce very thin bars with large gaps. If the chart looks distorted, reset Gap Width to 150% by typing 150 in the number box.
Gap Width changes affect only one series
In a clustered bar chart with multiple series, each series has its own Gap Width. To make all bars the same thickness, select each series one at a time and apply the same Gap Width percentage.
Chart type does not support Gap Width
Gap Width is available only for bar charts, column charts, and some line charts. It does not appear for pie charts, doughnut charts, or scatter charts. If you cannot find the slider, verify that your chart is a bar or column type.
| Item | Low Gap Width (0-50%) | High Gap Width (300-500%) |
|---|---|---|
| Bar thickness | Very thick bars | Very thin bars |
| Gap between bars | Almost no gap | Large gap |
| Best use case | Few categories, dense data | Many categories, sparse data |
| Readability | Bars dominate the chart | Gaps dominate the chart |
After adjusting Gap Width, you can further refine the chart by changing the bar fill color, adding data labels, or adjusting the axis scale. The Gap Width setting works independently of those other formatting options. Try setting Gap Width to 80% for most business presentations to create balanced bars with visible separation.