- single choice questions
- mask questions (e.g. Gender, Yes/No)
Pie charts are best used when you are presenting a share of something, ideally items explaining a single variable to benefit readibility and assessment.
Logically, all shares in a pie chart should thereby add up to 100%. For example, when you have binary survey responses, e.g., yes/no question types, or questions with only a few answer options/categories. Overloading a pie chart with too many categories, i.e., 6 or more, makes it hard to identify labels as well as shares and should be avoided.
When it comes to data types, nominal data such as demographics, i.e., data without an order or ranking, as well as ordinal data such as likert scale ratings, i.e., data with an order or ranking, can be visualised using pie charts.
Nominal data can be arranged clockwise from largest to smallest share and ordinal data can be arranged clockwise according to ranking or rating scale.
In order to increase distinction between shares in a pie chart, strong colour contrasts or colour shades can help to achieve this.
Pie charts are a nice and visually appealing solution if you are trying to show general trends rather than specific accurate data.
General Tip: Avoid including "Other" as an option choice, as an answer as different responses will not be displayed in a pie chart, but will be shown as "Other".