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ABC analysis (Pareto) calculator

Find out which products or customers drive your revenue. Paste a list from Excel, choose the criterion and limits and get each item’s class, a Pareto chart and a ready spreadsheet.

Educational simulation. Not investment advice. Results are estimates based on the data you enter and do not replace advice from a qualified professional.

Reviewed on Nov 2, 2026

Example: one month of sales of 15 products in a convenience store. Paste your own list from Excel or a sales report.

See what was read
Class limits

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Class A—
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Pareto chart

Each bar is an item, largest first, colored by class. The line shows the cumulative share of the total.

Tap the chart to see the values.

Items vs. value by class

Share of items and share of the total in each class.

Tap the chart to see the values.

Ranked items

List sorted by the chosen criterion, with share, cumulative share and class.

Next step

Take this page’s results to another calculator with the fields already filled in.

Find the order quantity and reorder point of item #1 →Simulate the sales mix and margin →

The summary lists your inputs, results, formulas, assumptions and sources. The full report also includes the charts and interpretations, in color. In the print dialog, choose Save as PDF.

Method, assumptions and sources

Formulas

Share = item value ÷ total; cumulative = sum of shares from item 1 to it (descending order)
Class A if the cumulative share before the item < limit A; B if < limit A + limit B; otherwise C

Assumptions and limits

  • Items with zero or negative value on the criterion are left out. With a single numeric column, it is used as the ranking value.
  • When moving to the inventory calculator, item #1’s monthly sales are its units divided by the chosen period, and unit cost is (revenue − margin) ÷ units.

Official sources and references

Frequently asked questions

What is ABC analysis?

It ranks products, customers or suppliers from largest to smallest and splits them into three groups by their weight in the total. Class A holds the few items that make up most of the result; class C, the many that add up to little. It shows where to focus inventory, purchasing and sales effort.

How do I read the example result?

In the example, 6 of 15 products (40% of the list) make up 82.3% of $30,620 in revenue; soda alone accounts for 24.8%. Class B has 5 products (13.0%) and class C has 4 products that bring in only 4.7% of revenue. In the table, the Class column shows each item’s group.

Where do I get the data?

From the product sales report of your point-of-sale or inventory system, ideally covering 3 to 12 months to smooth out seasonality. Export to Excel with name, units, revenue and, if available, margin (revenue minus cost of goods), then paste it or load the file.

Why 80/15/5?

It is the most common split and follows the Pareto principle, but it is not a rule. Businesses with many similar items use 70/20/10 or 50/30/20 to keep class A smaller. What matters is using the same limits every time so periods can be compared.

Should I discontinue class C items?

Not necessarily. Some C items round out the assortment, draw customers in or carry a high margin. Before cutting, rerun the analysis by margin and by units, check whether the item sells together with A items and weigh the shelf space and cash it ties up.

Can I use it for customers?

Yes. Paste your customer list with each customer’s revenue. Class A shows who the business depends on: if a few customers make up most of revenue, losing one is a big risk and it pays to diversify.

What are the limits of this calculator?

It ranks by one criterion at a time and ignores seasonality, the growth of new products and margin after variable costs. For purchasing decisions, combine it with the inventory and reorder point calculator.

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ABC analysis: how to rank products and customers with the Pareto principle

ABC analysis sorts the items on a list (products, customers, suppliers) from largest to smallest and shows how much each group contributes to the total. It rests on the Pareto principle: in many businesses, about 20% of items drive 80% of the result.

How to build it

Add up each item’s revenue (or units, or margin) for the period, sort from largest to smallest and compute the cumulative percentage. Items up to 80% of the cumulative total are class A; up to 95%, class B; the rest, class C. Adjust the limits to your business.

Example

In the calculator’s convenience store, 6 of 15 products (40%) make up 82.3% of $30,620 in revenue: soda, beer, rice, milk, coffee and cooking oil. Five products are class B (13.0%) and four are class C (4.7%).

ClassItemsRevenueHow to manage
A6 (40%)82.3%Never run out, watch prices, negotiate often
B5 (33%)13.0%Periodic review, moderate stock
C4 (27%)4.7%Buy less, simplify or replace

Revenue, units or margin

Ranking by revenue shows where sales come from; by units, what moves most through inventory; by margin, what drives profit. Compare all three before discontinuing a product: a class C item by revenue may be what brings customers in.