Introduction
A pie chart shows how parts add up to a whole. Each slice stands for one group, and the size of the slice shows how big that group is.
Type a label and a value for each group. The calculator adds up your values, finds the percent for each one, and works out the angle of each slice in degrees. Then it draws the chart right away.
You can enter data by hand or paste it in from a list. You can pick colors, add a title, turn your pie into a donut, pull out one slice, and move labels inside or outside. When you like the result, save it as an SVG, a PNG, or a CSV file, or print it.
The calculator also shows the steps. You can see the total, the fraction for each group, and how that fraction turns into a percent and an angle. That makes it handy for homework, class projects, reports, and quick charts at work.
How to use our Pie Chart Calculator
Type in your category names and their values. The pie chart calculator works out each slice's percentage and angle, draws your pie chart, and shows the math step by step.
Manual Entry or Bulk Paste: Pick Manual Entry to type each row by hand, or Bulk Paste to drop in a list you already have.
Number of Sectors: Set how many slices you want, from 1 to 26. Rows are added or cut from the bottom.
Label: Name each slice, like "Sales" or "Rent".
Value: Type the number for that slice. It must be zero or more. The percent and angle fill in on their own.
Color: Click the color box to pick a shade for that slice.
Remove / Add Row: Use the × button to delete a row, or Add Row to put in a new one.
Paste your data: In Bulk Paste mode, put one slice per line, like Marketing, 15.
Auto-detect delimiter: Leave this on and the tool finds the comma, tab, or semicolon. Turn it off to pick the delimiter yourself.
Parse Data: Click this to turn your pasted lines into table rows.
Chart Title: Type a title for your chart, or leave it blank for none.
Chart Type: Choose a full pie chart or a donut chart with a hole in the middle.
Inner Radius: For donut charts only, drag this to make the hole bigger or smaller.
Sorting: Keep your rows in the order you typed them, or sort slices from biggest to smallest.
Start Angle: Set where the first slice begins. 0° starts at the top, like 12 on a clock.
Label Position: Put labels inside the slices, outside them, on callout lines, or hide them and use only the legend.
Show sector name, percentage, raw value: Tick what you want printed on each slice label.
Label Precision: Choose how many decimal places show in the labels, from 0 to 4.
Show legend: Tick this to show a key that matches colors to names.
Legend orientation: Put the legend on the right side or below the chart.
Explode Sector: Type a slice number and click Apply Explode to pull it out of the pie. Click Remove Explode to push it back.
Color Scheme: Pick a ready-made color set, such as Pastel, Vibrant, or High Contrast.
Slice Border Width and Color: Set how thick the line between slices is and what color it is.
Gradient fill: Tick this to give slices a soft shaded look.
Font Family and Font Size: Choose the look and size of the text on your chart.
Animation Speed: Pick how fast the slices draw in, or choose None for no motion.
Calculate and Reset: Click Calculate to redraw the chart, or Reset to go back to the sample data.
Expand, Print, and Export: Open a bigger view, print the chart with its data table, or save your work as SVG, PNG, or CSV.
What Is a Pie Chart?
A pie chart is a circle split into slices. Each slice stands for one part of a whole group. The bigger the slice, the bigger that part is. Pie charts are used to show how something is shared out, like a budget, survey answers, or how you spend your day.
Parts of a Pie Chart
- Sector (slice): one category, like "Sales" or "Rent".
- Central angle: the angle of the slice at the middle of the circle.
- Label: the name, value, or percent written on or next to the slice.
- Legend: a key that matches each color to a category name.
How Pie Chart Percentages and Angles Are Found
First, add all your values to get the total. Then use these two formulas for each category:
- Percentage = (value ÷ total) × 100%
- Angle = (value ÷ total) × 360°
Example: if Sales is 20 out of a total of 100, then 20 ÷ 100 = 0.2. That is 20% of the pie and an angle of 72°.
All the percents should add to 100%, and all the angles should add to 360°. Sometimes rounding makes the total look like 99.9% or 360.1°. That small gap is normal.
When to Use a Pie Chart
Pie charts work best when you have one whole thing split into a few parts, usually 2 to 7 slices. They make it easy to see which part is biggest and which is smallest.
Pie charts are a poor choice when you have many small slices, when slices are close in size, or when values can be negative. In those cases a bar chart is clearer. A pie chart also cannot show change over time, so use a line chart for that.
Pie Chart vs. Donut Chart
A donut chart is the same as a pie chart, but the middle is cut out. The math is exactly the same. The empty center is often used to show the total or a title.
Tips for a Clear Pie Chart
- Sort slices from big to small so they are easy to compare.
- Use colors that are easy to tell apart, and add a legend.
- Show the percent on each slice so readers do not have to guess.
- Pull out (explode) one slice only when you want to point it out.
- Group tiny slices into one "Other" slice to cut clutter.