Comparison
| Need | Pie chart | Bar chart |
|---|---|---|
| Show a few shares of one total | Strong | Strong |
| Compare similar values precisely | Weak | Strong |
| Display many categories | Weak | Strong |
| Include negative values | Invalid | Strong |
| Emphasize the idea of a whole | Strong | Moderate |
A practical rule
If the sentence contains “share of the total,” a pie or donut may work. If it contains “largest,” “smallest,” “rank,” or “difference,” bars are safer. For accessibility, do not rely on color alone: keep labels and surrounding text explicit.
Frequently asked questions
Are bar charts more accurate than pie charts?
People generally compare aligned lengths more precisely than angles and areas, so bars are better for close values.
When is a pie chart appropriate?
Use it for a small number of distinct, non-overlapping parts that together represent one total.
Can a pie chart show negative values?
No. Negative values do not have a meaningful slice of a whole. Use a bar chart instead.