Circular charts: definition and use cases depending on their type

A circular chart represents numerical proportions where data is displayed as sectors of a circle. Do you need to create insightful visualizations? Then, circular charts provide an alternative to traditional stacked bar charts and tables, offering an easy-to-understand format that highlights key proportions at a single glance. While pie charts remain the most recognizable type, circular charts encompass various styles that serve different analytical purposes.

What is a circular chart?

A circular chart divides a circle into proportional segments, with each segment representing a percentage of the total data set. The complete circle represents 100% of the data, and each slice or sector corresponds to a specific proportion. These visualizations excel at displaying categorical data and making proportional comparisons intuitive for users. The circular layout naturally draws the eye to size differences between segments, making it particularly effective for highlighting significant proportions within your data structure.

What are the types of circular charts?

Several distinct types of circular charts serve different visualization needs:

• Pie charts: The traditional form where sectors extend from the center to the edge
• Donut charts: Similar to pie charts but with a hollow center, making it easier to compare segments
• Radial charts: Display data in a circular pattern with varying radius lengths
• Clock charts: Utilize a 12-hour layout to represent time-based data
• Sunburst charts: Show hierarchical data in concentric circles

Applications and use cases of circular charts, depending on their nature

Note that each circular chart type has specific applications!

How to interpret circular chart data?

Reading circular charts accurately requires remembering that the size of each sector corresponds directly to its percentage of the total, with the central angle of each slice proportional to the frequency it represents. For precise interpretation:

• Start from the largest segment, typically positioned at the 12 o'clock position

• Compare relative sizes of segments clockwise

• Use data labels to verify exact values

• Consider the total sum represented by the complete circle

How to measure angles in circular charts?

Measuring angles accurately ensures precise data representation. The formula for calculating sector angles is: Angle = (Value / Total Sum) × 360°

For example, in a data set totaling 1000:

• A value of 250 would occupy a 90° angle (250/1000 × 360)
• A value of 500 would span 180° (500/1000 × 360)

This mathematical foundation helps maintain accuracy in visual representation and ensures data integrity across all circular chart variations.

How to customize a circular chart?

Master-level circular chart design combines technical precision with visual appeal. Begin by selecting distinct colors for each segment, ensuring sufficient contrast between adjacent sectors to make differentiation effortless for viewers. Meaningful labels should be positioned strategically around the chart, incorporating both category names and corresponding percentages to provide immediate value recognition.

Note: For emphasizing crucial data points, consider using exploded sections that physically separate important segments from the main body of the chart, drawing immediate attention to significant findings. Complete your visualization with a well-structured legend that provides categorical reference points, positioned where it won't interfere with the chart's visual flow but remains easily accessible.

These customization techniques work together to create a polished, professional presentation that effectively communicates your data story.