Box Plot Maker

Draw a box & whisker plot from your data — download it or compare two sets

Enter your numbers to generate a box and whisker plot instantly. The chart shows the quartiles, median, whiskers and any outliers, and you can download it as a PNG or add a second data set to compare.

Enter Your Data Points

Textbooks differ — pick the method yours uses.

Five Number Summary

Minimum9
Q1 (25th)21
Median29.5
Q3 (75th)37.5
Maximum48
Interquartile range (IQR)16.5
Count (n)20
Outliers (1.5 × IQR rule)None

Additional Statistics

Mean (average)29.1
Mode21
Range39
Sum582
Std deviation (sample)10.8235
Std deviation (population)10.5494
Variance (sample)117.1474
Mean absolute deviation8.9
Coefficient of variation0.3719
Standard error of the mean2.4202
10th percentile16.5
90th percentile42.2
Lower inner fence (Q1 − 1.5·IQR)-3.75
Upper inner fence (Q3 + 1.5·IQR)62.25

Box & Whisker Plot

Histogram

Step-by-step solution

Export & Share

The share link reproduces your exact data and settings — paste it in an email, chat, or assignment and anyone who opens it sees the same results.

Saved Datasets

Saved to this device only (browser local storage). Use a share link to move data between devices.

What a box plot shows

A box plot (or box-and-whisker plot) is a compact picture of a distribution built from the five-number summary. The box spans from Q1 to Q3, so it covers the middle 50% of the data, and the line inside the box marks the median. The whiskers reach out to the most extreme values that still fall within 1.5 × IQR of the quartiles, and any points beyond the whiskers are drawn individually as outliers.

How to read it

The width of the box is the interquartile range — a wider box means more spread in the central half of the data. The position of the median line within the box reveals skew: a median sitting toward the left (lower) side indicates right-skewed data, and vice versa. Long whiskers or isolated outlier points highlight extreme values that may deserve a closer look.

Comparing groups

Box plots are at their most useful when placed side by side. Use the "Compare second dataset" button to overlay a second group and instantly see differences in centre, spread and skew — for example, comparing test scores between two classes or response times before and after a change. When you have the chart you want, download it as a PNG to drop into a report or assignment.

Frequently asked questions

How do you make a box plot from a five-number summary?

Draw a box from Q1 to Q3 with a line at the median, extend whiskers to the furthest values within 1.5 × IQR of the quartiles, and plot any points beyond the whiskers as outliers. This tool does it all automatically.

What do the whiskers represent?

The whiskers reach to the smallest and largest values that are still within 1.5 × IQR of Q1 and Q3. Points outside that range are shown as individual outlier markers.

Can I compare two data sets on one chart?

Yes. Add a second data set with the compare button and the box plot overlays both groups so you can compare their centre and spread directly.

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