How to make a Pareto chart
- List each category with its count, such as
Late delivery, 42, or paste a raw list of category names to be counted. - The categories are sorted from largest to smallest, and the cumulative percentage is calculated.
- Read where the line crosses 80%: the bars to its left are the “vital few” to fix first.
- Download the chart or copy the Pareto table into your report.
Worked example: customer complaints
| Complaint | Count | % | Cumulative % |
|---|---|---|---|
| Late delivery | 42 | 45.7% | 45.7% |
| Damaged item | 18 | 19.6% | 65.2% |
| Wrong item sent | 11 | 12.0% | 77.2% |
| Poor packaging | 7 | 7.6% | 84.8% |
| Others (4 types) | 14 | 15.2% | 100% |
Four of eight complaint types cause about 85% of all complaints, and late delivery alone causes almost half. Fixing delivery first will have the biggest impact.
Tips
- Measure what matters: counts are common, but cost or time lost can tell a different story.
- Keep categories distinct and specific; vague ones like “misc” hide the real causes.
- Re-draw the chart after making changes to confirm the top bar has shrunk.
Working with measurements rather than categories? Use the histogram maker to see their distribution.
Common mistakes to avoid
- Not sorting the bars. A Pareto chart must run from the largest category to the smallest, with “Other” last.
- A cumulative line that doesn’t reach 100%. The last point must be 100%; if not, a category is missing.
- Too many tiny categories. Merge them into “Other” so the vital few stand out.
- Treating 80/20 as exact. Report the real split from your data, such as “3 causes = 72% of defects”.
Do it in other software
| Software | How |
|---|---|
| Excel 2016+ | Select the categories and counts, then Insert › Insert Statistic Chart › Pareto. |
| Google Sheets | Sort the counts in descending order, add a cumulative % column, then make a combo chart (columns + line on a second axis). |
| Python | Sort a pandas Series, plot it as bars, then plot series.cumsum() / series.sum() on a twin axis. |
Related tools: Histogram Maker, Frequency Distribution Table Maker, Box Plot Maker, Descriptive Statistics Calculator and Relative Frequency Histogram.