What is a Bar Chart?
A bar chart represents data using rectangular bars, where the length or height of each bar is proportional to the values it represents. It is the gold standard for representing discrete, categorical comparisons, allowing users to make instantaneous size comparisons.
When should you use a Bar Chart?
Bar charts are best suited for comparing values across separate groups. You should choose a bar chart when:
- You want to compare nominal categories (e.g. products, countries, departments).
- The categories are unrelated and do not belong to a sequential timeline.
- You want to display distribution structures using grouped or stacked subdivisions.
Grouped vs. Stacked Bar Charts
- Grouped Bar Charts: Display columns side-by-side. Excellent for direct comparisons of individual sub-items across key clusters.
- Stacked Bar Charts: Pile segments on top of one another to show parts of a cumulative whole. Ideal when the total value of each category is of primary importance.
Designing High-Converting Bar Charts
Follow these tips to keep your bar charts clean and highly legible:
- Always start at zero: Changing the Y-axis minimum to anything other than zero on a bar chart visually distorts the relative sizing of the bars, making comparisons inaccurate.
- Sort your bars logically: Arrange categories from highest to lowest value to help viewers identify top and bottom performers at first glance.
- Keep labels horizontal: Rotate axes or use horizontal layouts if column label texts are long, preventing diagonal truncation.