Distribution
Box Plot
Shows distribution through quartiles, median, whiskers, and outliers.
Score Distribution by Class
Three class sections, 20 students each
View data (60 rows)
| Class | Score |
|---|---|
| A | 58 |
| A | 62 |
| A | 65 |
| A | 68 |
| A | 70 |
| A | 72 |
| A | 73 |
| A | 74 |
| A | 76 |
| A | 77 |
| A | 78 |
| A | 79 |
| A | 80 |
| A | 82 |
| A | 83 |
| A | 85 |
| A | 87 |
| A | 89 |
| A | 92 |
| A | 96 |
| B | 50 |
| B | 55 |
| B | 58 |
| B | 60 |
| B | 62 |
| B | 64 |
| B | 65 |
| B | 67 |
| B | 68 |
| B | 70 |
| B | 71 |
| B | 72 |
| B | 74 |
| B | 75 |
| B | 77 |
| B | 78 |
| B | 80 |
| B | 82 |
| B | 85 |
| B | 90 |
| C | 70 |
| C | 74 |
| C | 77 |
| C | 80 |
| C | 82 |
| C | 84 |
| C | 85 |
| C | 86 |
| C | 87 |
| C | 88 |
| C | 89 |
| C | 90 |
| C | 91 |
| C | 92 |
| C | 93 |
| C | 94 |
| C | 95 |
| C | 96 |
| C | 97 |
| C | 99 |
Use a box plot when…
- Comparing distributions across groups
- Spotting outliers
- Summarizing spread
Avoid when…
- Showing exact distribution shape (use violin)
- Small samples (<10 points)
Data it needs
| Property | Value |
|---|---|
| Min Rows | 10 |
| Min Columns | 1 |
| Column Types | number |
| Notes | Optionally a category column for grouped box plots. |
Visual anatomy
Marks
rectanglelinecircle
Channels
position-ylength
Axes
x-categoricaly-quantitative
Guiding principles
Consider instead
Common mistakes
Not explaining whisker definition
Hiding multimodal distributions
History
Invented by John Tukey in 1970 as part of exploratory data analysis.
Accessibility notes
Provide the five-number summary (min, Q1, median, Q3, max) as text — and announce it per group when the chart is grouped, not just for the whole chart.
Related reading
Got data? Let's see what works.
Drop your CSV. You'll get a Box Plot plus four alternatives - ranked by which one actually fits your data best.