Pick the chart by the question
Bar to compare, line for time, pie for 2-5 parts, number for one value.
From refactoring-ui: Data Visualization, “Choosing the Right Chart Type”.
Same data, five charts
Pick a dataset, then flip the chart type.
Data
Chart
Traffic by deviceWhat share is mobile?
Two-slice pie vs a number
Drag the value; compare how fast each reads.
Two-slice pieBad
<PieChart data={[a, b]} />Big numberGood
73% of users completed onboarding
<strong>73%</strong>12 categories, three charts
Add categories, then search for a small topic.
PieBad
Vertical barsBad
Sorted bars + OtherGood
Why it matters, pros and cons
Why it matters
The eye reads position and length fastest, angle and area slowest. When the answer is one number, show the number.
Pros
- The answer lands in one glance.
- Sorted bars give a free ranking.
- A big number is just text.
Cons
- A 2-3 slice pie wins when "about a quarter" matters.
- A lone number drops context; add the change.
- "Other" hides the tail; let readers search it.