# Box Plot Maker - Box and Whisker Plot with Quartiles

> Box and whisker plots from pasted columns: Tukey, TI-84, Excel INC/EXC or Minitab quartiles, 1.5×IQR and 3×IQR outliers, mean, notches, PNG/SVG export.

- URL: https://qilingtools.com/en/math/box-plot
- Category: Math Tools (https://qilingtools.com/en/math)
- Tags: [Math](https://qilingtools.com/en/tags/math), [Statistics](https://qilingtools.com/en/tags/statistics), [Charts & Visualization](https://qilingtools.com/en/tags/chart)
- Last updated: 2026-10-26
- Price: Free, no sign-up
- Privacy: Runs locally in the browser; files are never uploaded

Paste a few columns from Excel or any spreadsheet — one group per column, with an optional header row — and get side-by-side box plots, or put one group per line instead. The box runs from the first quartile Q1 to the third quartile Q3 with a bold line at the median; by default the whiskers reach the furthest data points within 1.5 interquartile ranges (IQR), and points beyond are flagged as mild outliers (1.5–3 × IQR, open circles) or extreme outliers (more than 3 × IQR, stars). You can extend the whiskers to the minimum and maximum instead, or change the factor k. Quartiles are computed differently by different software, which matters for small samples, so five methods are offered: Tukey’s hinges, Moore & McCabe (used by the TI-84 and many textbooks), Excel’s QUARTILE.INC and QUARTILE.EXC, and Minitab. The chart can show the mean (diamond), notches for a 95% interval around the median and all data points with jitter, horizontally or vertically, with a title and axis label, and exports as PNG or SVG. The table below lists each group’s count, five-number summary, IQR, mean, standard deviation, fences, whisker ends and outliers, ready to copy.

## How to use

1. Paste your data: one group per column with optional names in the first row (or switch to one group per line)
2. Choose the quartile method and whisker rule, and turn on the mean, notches or data points if you like
3. Read the box plot and the statistics table, then export PNG/SVG or copy the table

## Features

- Several groups side by side, pasted straight from spreadsheet columns
- Five quartile methods: Tukey, TI-84, Excel INC, Excel EXC and Minitab
- Mild (1.5×IQR) and extreme (3×IQR) outliers marked separately, factor adjustable
- Optional mean marker, median notches and jittered points
- Horizontal or vertical, with custom title and axis label
- Five-number summary, IQR, mean, standard deviation, fences and whisker ends
- Copy the statistics table back into a spreadsheet
- Export a sharp PNG or vector SVG

## FAQ

### How do I read a box plot?

The box covers the middle 50% of the data: its lower edge is Q1, its upper edge Q3, and its length is the interquartile range IQR = Q3 − Q1. The line inside is the median. Whiskers reach the furthest points still within Q1 − 1.5×IQR and Q3 + 1.5×IQR, and anything beyond is drawn as an outlier. A longer box means more spread, an off-centre median suggests skew, and comparing boxes shows differences between groups at a glance.

### Why do different programs give different quartiles?

There is no single definition of a quartile. For the 11 values 6, 7, 15, 36, 39, 40, 41, 42, 43, 47, 49, a TI-84 (which leaves the median out of both halves) gives Q1 = 15 and Q3 = 43; Tukey’s hinges and Excel’s QUARTILE.INC give 25.5 and 42.5; Excel’s QUARTILE.EXC and Minitab, which interpolate at position (n+1)p, give 15 and 43. Pick the method that matches your textbook or software.

### How are outliers identified?

The usual rule is Tukey’s: compute the IQR, and any point below Q1 − 1.5×IQR or above Q3 + 1.5×IQR is an outlier; if it’s also beyond the outer fences at 3×IQR it’s an extreme outlier. The plot uses different symbols for the two and the table lists the fences. You can change the 1.5 factor, or switch the whiskers to min–max, which flags no outliers.

### What are notches for?

A notch shows an approximate 95% confidence interval for the median, median ± 1.57×IQR/√n. If the notches of two boxes don’t overlap, that’s rough evidence the medians differ. With small samples the notch can be wider than the box; the plot then keeps it within the box.

## Related tools

- [Graphing Calculator](https://qilingtools.com/en/math/graph): Free online function graphing calculator: type sin(x), x^2 or 1/x and see the curve at once, with several functions, parametric and polar curves, PNG export.
- [Scientific Calculator](https://qilingtools.com/en/math/calculator): Free online scientific calculator: type 2*(3+4)^2, sin(pi/6) or log(8,2) and see the answer as you type, with degrees or radians and a history list.
- [Equation Solver](https://qilingtools.com/en/math/equation): Free online equation solver: enter coefficients for linear, quadratic (with discriminant, vertex and complex roots) and cubic equations, plus 2×2 systems.
- [Fraction Calculator](https://qilingtools.com/en/math/fraction): Free online fraction calculator: add, subtract, multiply and divide fractions with automatic reduction, plus fraction ↔ decimal with repeating digits.
- [Percentage Calculator](https://qilingtools.com/en/math/percentage): Free online percentage calculator: X% of Y, X as a percent of Y, increase and decrease, a value after a percentage change and the original behind it.
- [Prime Factorization](https://qilingtools.com/en/math/prime): Free online prime factorization: factor an integer with exponents, list every divisor and their sum, test primality with neighbouring primes, or list a range.
- [GCD and LCM](https://qilingtools.com/en/math/gcd-lcm): Free online GCD and LCM calculator: works with two or more integers, says whether they are coprime, shows each prime factorization and every Euclidean step.
- [Statistics Calculator](https://qilingtools.com/en/math/statistics): Free online statistics calculator: paste a data set for the mean, median, mode, range, quartiles, variance, standard deviation, standard error and outliers.
