Pie Chart Maker

What a pie chart shows

A pie chart maps each positive value to an angle around a 360° circle. If a category has value v and all displayed values sum to T, its central angle is 360 × v / T, while its displayed percentage is 100 × v / T. A donut chart uses the same proportions and removes the center; it does not change the underlying comparison.

In this example, the total is 100. Product therefore takes 45 / 100 × 360 = 162°. The tool accepts zero values but omits them from the visible circle. It rejects negative, missing and non-finite values because they do not define ordinary parts of a whole, and it requires at least one positive value.

When to use another chart

Pie charts are easiest to read with a small number of clearly different slices. A bar chart is usually better when values are close, there are many categories, precise comparisons matter, or the categories are not parts of one total. A line chart is more appropriate for change over time. Avoid adding percentages that already overlap or double-count, because a polished circle cannot repair an invalid total.

Color, labels and accessibility

Color alone should not carry the meaning. Keep the legend or visible slice labels, review the accompanying table, and use the colorblind-friendly palette when the chart will be shared broadly. Very small slices may not have room for text inside the circle; their exact label, value and percentage remain available in the legend and data table. SVG is useful for editing and sharp print output. PNG is a fixed 1200 × 800 image suitable for slides, documents and social posts.

The chart is generated with browser SVG and Canvas APIs. No chart data is sent to an external chart service. Funnel progress is kept temporarily in this tab’s session storage and can be cleared by starting over or closing the tab.

For further guidance, see Datawrapper’s advice on creating pie charts with no more than a few parts, the W3C’s accessible data-table tutorial, and MDN’s reference for describing SVG graphics with <desc>.