Annotations & Text

Matplotlib is a Python library for creating charts and visualizations — and annotations let you write labels directly on a chart and draw arrows pointing at the exact data points that matter.

Learn Annotations & Text in our free Matplotlib course — a beginner-friendly interactive lesson with worked examples, a practice exercise and a quick reference.

Part of the free Matplotlib course at LearnCodingFast — hands-on lessons with examples you run in your browser, plus practice exercises and a quick quiz.

In this lesson you'll add free-floating text with plt.text(), point arrows at a peak with ax.annotate(), and wrap labels in a styled box.

The simplest way to write on a chart is plt.text(x, y, "label") . The first two arguments are data coordinates — where on the chart the text begins — and the third is the string to show.

What you'll see: the rising curve with the words "x squared" sitting just beside the point (3, 9). The text floats at that data location with no arrow — that's the difference from annotate().

To draw an arrow from a label to a target point, use ax.annotate() . The xy argument is the point the arrow points to ; xytext is where the label sits; and arrowprops describes the arrow itself.

What you'll see: the zig-zag line with the text "Big jump" floating at (2.5, 32) and a thin arrow stretching from those words down to the high point at (4, 30) — drawing the eye straight to it.

A common use is highlighting the maximum . You can find the peak with Python's max() and feed its coordinates into annotate() .

What you'll see: the line chart with a red arrow pointing at the tallest dot (x=4, y=12) and the label "Max = 12" beside it — computed automatically from the data, not hard-coded.

To make a label stand out, draw a box behind it with the bbox argument. Pass a dictionary that sets the box shape ( boxstyle ), fill color ( facecolor ), and transparency ( alpha ).

What you'll see: the line chart with the word "Important!" sitting inside a soft, rounded, semi-transparent yellow box near (1, 4) — far more eye-catching than bare text.

Replace each ___ to point an arrow at the data point (3, 9).

You left out arrowprops . Add arrowprops=dict(arrowstyle="->") to draw the arrow.

xy and xytext use data coordinates. Pick values inside your axis ranges, not pixels.

Plot monthly visitors, then point a boxed arrow at the busiest month.

Lesson 13 complete — your charts can talk now!

You placed plain text with plt.text(), pointed arrows at a peak with ax.annotate(), and boxed a label with a bbox dictionary.

🚀 Up next: Plotting with Dates — put real calendar dates on the x-axis.

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