Grouped Bar Charts

A grouped bar chart, also called a clustered bar chart, shows two or more data series side by side within each category. To read one, match each colour to its series using the legend, compare the bars inside a cluster to see which series leads, then follow one colour across clusters to see how that series changes.

A grouped bar chart — also called a clustered bar chart — places several bars side by side within each category so you can compare multiple data series at once. Where a plain bar chart shows one value per category, a grouped chart shows several: each category becomes a small cluster of bars, one bar per series, with the series distinguished by colour. It is the go-to format when you want to ask how do these series compare, both within each category and across categories? — for example, two or three measures recorded for the same set of groups.

How a grouped bar chart works

Categories run along one axis — typically the horizontal axis for vertical bars. Within each category, the chart draws one bar per series, packed together as a tight cluster with a gap separating the clusters. A shared colour identifies each series across every category, and a legend maps colours to series. The value axis starts at zero, so a bar twice as tall really does represent twice the value. Because all the bars sit on the same baseline, you can read two comparisons from one picture: the bars within a cluster against each other, and the same-coloured bar across clusters.

That dual reading is the format's strength and its main demand on the reader. Keep the number of series small and the colours distinct, and both comparisons stay easy. Let either grow and the clusters turn into a thicket.

When to use a grouped bar chart

• Comparing a few series across categories. Two to four measures recorded for the same set of groups, where you want them side by side rather than summed.
• The individual values matter. Grouped bars keep every value on the same baseline, so each one can be read and compared precisely.
• Within-category contrast is the point. "In this category Series 1 leads, but in that one Series 2 does" is a takeaway grouped bars show clearly.
• No meaningful total. When the series are not parts of a whole and adding them would be nonsense, side-by-side bars are correct where stacking would mislead.

Grouped vs. stacked bars

The two are easy to confuse because both show multiple series. The difference is what each makes easy. A grouped chart sets the bars side by side, so every value rises from the same baseline and direct comparison is accurate — but the total for a category is not shown. A stacked chart piles the series into one bar, so the total is obvious and you can see each part's contribution to it — but only the bottom segment starts at zero, which makes comparing the upper segments harder. Choose grouped when comparison matters most; choose stacked when composition and totals matter most.

How to read a grouped bar chart

First read the legend so you know which colour is which series. Then pick a reading direction. To compare series within a category, look at the bars in a single cluster and judge their heights against each other. To track one series across categories, follow a single colour from cluster to cluster — your eye will naturally line up the same-coloured bars. Use the value axis, which starts at zero, to read magnitudes, and lean on data labels for anything that looks close. Because the bars share a baseline, height differences are trustworthy in a way that pie or radar comparisons are not.

Step by step

1. Read the title and axis labels so you know what the categories are and what unit the bars measure.
2. Read the legend. Each colour is one series, and it repeats in every cluster.
3. Check the baseline. Bars should start at zero; if they do not, height differences are exaggerated.
4. Compare within a cluster: which series is highest in this category, and by how much?
5. Compare across clusters: follow one colour from left to right to see how that series changes.
6. Look for reversals: categories where the order of the bars flips are usually the most interesting part of the chart.

Worked example: reading a clustered bar chart

A team tracks support tickets per region for two years:

As a clustered bar chart there are three clusters (North, South, West), each with two bars. Within each cluster you can see that this year's bar is taller in North and West but shorter in South: the one reversal, and the first thing worth asking about. Across clusters, following this year's colour shows West is clearly the largest region, and the West cluster has the biggest gap between its two bars (70 tickets, or 50% more). Note what the chart does not show directly: the combined total for each region. If totals were the point, a stacked bar chart would make them visible.

Grouped vs. stacked: side-by-side summary

For a deeper comparison with examples, see stacked vs grouped bar chart.

Variants

Grouped bars can be drawn vertical (columns) or horizontal; horizontal is handy when category names are long. Small multiples — repeating a simple bar chart once per series in a grid — are a clean alternative when you have more series than a single cluster can hold. And some charts combine approaches, grouping a couple of clusters that are each lightly stacked, though that quickly becomes hard to read. For most cases, a straightforward cluster of two to four bars per category is the clearest choice.

Common mistakes to avoid

Make a grouped bar chart

Ready to build one? The stacked bar chart maker handles grouped (clustered) bars too — enter your categories and series or paste a CSV, switch between grouped and stacked, recolour, and export a PNG or SVG — free, no signup, no watermark. For a single series, the simpler bar chart maker is quicker, and if you are unsure which chart fits your data, start with how to choose a chart.

Frequently asked questions

What is a grouped (clustered) bar chart?

A grouped bar chart, also called a clustered bar chart, is a bar chart that shows two or more data series for each category as bars placed side by side. Each series has its own colour, and a legend tells you which colour belongs to which series.

How do you read a clustered bar chart?

Start with the legend to match each colour to a series, then check the value axis and its baseline. Compare bars within one cluster to see which series is highest in that category, then follow one colour across clusters to see how that series changes from category to category.

What is the difference between a grouped bar chart and a stacked bar chart?

A grouped bar chart places the bars for each series side by side within a category, so you compare series directly. A stacked bar chart piles them on top of one another to show how parts add up to a total. Use grouped to compare values, stacked to show composition.

Is a clustered bar chart part of the bar chart family?

Yes. A clustered bar chart is a type of bar chart. It uses the same rectangular bars and zero baseline as a simple bar chart but shows more than one series per category. Spreadsheet tools such as Excel list it as Clustered Bar or Clustered Column under the bar chart options.

Is there a difference between a grouped and a clustered bar chart?

No. Grouped bar chart and clustered bar chart are two names for the same chart. Some tools also call it a side-by-side bar chart, a multiple bar chart or, for vertical bars, a clustered column chart.

Why do people use clustered bar graphs instead of normal bar graphs?

A normal bar graph can only show one value per category. A clustered bar graph shows several related values per category in one picture, such as this year and last year for each region, so readers can compare series within each category and across categories without switching between charts.