Simple comparisons Bar chart
Bar charts are the preferred method for comparing values across different categories for a single variable.
Visual styles for bar charts are detailed in our chart style guide on Notion (opens in a new tab)
An example of a standard bar chart
When to use a bar chart
You can use horizontal bar charts for most types of data.
For time series data, use vertical bar charts, also known as column charts.
When displaying time series data, refer to our Line chart guidance (opens in a new tab) and Column chart guidance (opens in a new tab) .
Axis
The axis on a bar chart should always start from zero.
If starting the axis above zero is necessary to clearly display the data, consider using a different chart type, such as a dot plot. For more information on axis scaling, read our Axes and gridlines guidance (opens in a new tab) .
Category order
Categories in your bar chart should follow a logical order, typically from largest value to smallest.
Read our Ordering in charts guidance (opens in a new tab) for more details on how to order categories.
Showing deviation
Bar charts can also be used to display deviations or differences. This might be the change in a value between two time periods or the deviation from an average.
This use case involves derived variables. For further information, refer to the What data to include (opens in a new tab) section in our Data visualisation principles guidance.
An example of a bar chart showing deviation
Bar charts with groups
Where the bars within a bar chart belong to high-level categories, they can be sorted into groups with subheadings. This adds structure and makes it easier for users to interpret values, especially when there are many bars.
You can use groups to show the values for different breakdowns of a population, for example, by age, gender, and ethnicity.
Make sure that both the groups and the bars within them follow a logical order. For more information, read the Charts with sub-groups section (opens in a new tab) in our Ordering in charts guidance.