A bar chart is the quickest way to compare amounts across categories, and creating a good one comes down to a few decisions: which way the bars run, how they are sorted, and where the axis starts. This guide covers what a bar chart is, the main types, the rules that keep one honest, and how to build one, with two live examples made from Statistics Canada's latest population estimates.
What is a bar chart?
A bar chart is a chart that compares values across categories using rectangular bars whose length is proportional to the value. Bars can run horizontally or vertically; vertical bars are usually called a column chart. Because readers compare lengths from a shared baseline, bar charts are among the most accurate chart types for judging differences between values.
Bar charts suit categorical data: countries, products, survey answers, age groups. Each category gets one bar, and the bars share one axis, so the comparison is direct.
A live example: where Canada grew in the past year
The chart below ranks Canada's 10 provinces and 3 territories by population change between 1 July 2025 and 1 July 2026, per 1,000 residents.
Three choices make it read quickly. The bars run horizontally, so long names such as Newfoundland and Labrador fit without rotating. They are sorted from largest to smallest, so the ranking is the first thing you see. And the one negative value, the Northwest Territories at -2.8, extends left of zero instead of being hidden.
The story is in the spread: Yukon grew by 24.5 people per 1,000 and Nunavut by 23.3, while Ontario, Quebec and British Columbia, home to three in four Canadians, added fewer than 3 each.
Bar chart or column chart?
The two are the same chart turned on its side, and the choice comes down to what sits on the category axis.
| Use | When | Example |
|---|---|---|
| Horizontal bar chart | Category names are words, or there are more than about 8 categories | Provinces, countries, products ranked by value |
| Column chart | The categories are time periods or a short ordered sequence | Years, months, age groups |
Time reads left to right, so years belong on a horizontal axis. Here is Canada's growth over 15 years, year to 1 July, as a column chart:
Growth peaked at 28.5 per 1,000 in 2024 and fell to 4.6 in 2026, the lowest in the period shown. The columns make the rise and fall readable at a glance without a line chart, because there is one value per year and each year is a separate period.
Types of bar charts
- Simple bar chart: one bar per category, like both examples above. Start here.
- Stacked bar chart: each bar is split into parts, showing totals and their composition. Only the first segment shares a baseline, so the parts after it are hard to compare.
- Grouped bar chart: two or more bars side by side per category, for comparing subgroups such as 2025 against 2026.
- Diverging bar chart: bars run left and right from zero, for gains and losses or agree and disagree.
- Lollipop chart: a thin line with a dot at the end. It reads like a bar chart with less ink, useful when there are many categories.
Rules for a bar chart people can trust
- Start the value axis at zero. A bar's length is the value. Cut the axis at 50 and a bar of 60 looks twice as long as a bar of 55. The UK government's Analysis Function chart guidance says not to break the numerical axis on bar charts, and a cut axis is one of the misleading chart tricks readers fall for most.
- Sort by value unless the categories have their own order. Alphabetical bars make readers hunt. Years, age groups and survey scales keep their natural order.
- Use one colour unless colour means something. In the provinces chart every bar is the same blue, because the categories are not groups. Use a second colour to highlight one bar, or for a real grouping.
- Label the values when exact numbers matter. Direct labels at the end of each bar save readers from tracing gridlines.
- Put the unit, period and source on the chart. "Change per 1,000 residents, July 2025 to July 2026" and a table number let the chart travel on its own.
How to create a bar chart in PlotSet
- Open the bar chart maker, or the column chart for time series.
- Prepare two columns: the category in the first and the value in the second, one row per bar.
- Upload a CSV, paste from a spreadsheet, or import a Google Sheet by its URL.
- Check that the label column is bound to labels and the number column to values.
- Sort the rows, set the colour, and turn on value labels.
- Publish for a live embed, or export a PNG, SVG or JPG.
The bar chart guide walks through each screen of the editor, and why bar charts still rule explains why this plain chart keeps beating more decorative ones.
FAQ
What is a bar chart used for?
A bar chart is used to compare amounts across categories, such as sales by product, population by country or answers to a survey question. It shows which categories are largest and smallest, and by how much.
What is the difference between a bar chart and a histogram?
A bar chart compares separate categories, and its bars can be reordered. A histogram shows the distribution of one continuous measure split into ranges, so the bars touch and their order is fixed.
Should a bar chart always start at zero?
Yes. The length of a bar encodes its value, so a value axis that starts above zero exaggerates differences. Line charts and dot plots can start elsewhere, because they encode position rather than length.
When should I use a horizontal bar chart?
Use horizontal bars when category names are long or when there are many categories, as in the provinces example above. Use vertical columns when the categories are time periods.
How many bars can a bar chart have?
There is no fixed limit, but past about 20 bars labels get crowded and the ranking gets harder to read. Show the top 10 or 15 and group the rest, or switch to a dot plot.
Data source for both charts: Statistics Canada, Table 17-10-0009-01, Population estimates, quarterly.
