80/20 calculator
80/20 Calculator — Measure Your Real Pareto Pattern
Test the 80/20 idea against your actual data. ParetoScope calculates each category's contribution and cumulative share so you can see where the concentration really occurs.
Interactive tool
Calculate your 80/20 concentration
Paste data, import CSV content, or use the sample dataset to see your vital few and cumulative contribution.
Turn raw data into a clear 80/20 decision
Edit, analyze, compare and export — everything runs in your browser.
Your Pareto insight
The first 3 categories account for 80.3% of the total. Start your investigation here rather than treating every category equally.
Why use ParetoScope?
Use actual data instead of assuming the ratio is exactly 80/20.
See which categories cross a chosen cumulative contribution threshold.
Understand the difference between a heuristic and your measured distribution.
Turn the result into a practical prioritization view.
Common use cases
Top customers by revenue
Rank your data, identify the largest contributors, and focus improvement work where it has the greatest potential impact.
Products driving sales
Rank your data, identify the largest contributors, and focus improvement work where it has the greatest potential impact.
Defects driving quality problems
Rank your data, identify the largest contributors, and focus improvement work where it has the greatest potential impact.
Tickets driving support workload
Rank your data, identify the largest contributors, and focus improvement work where it has the greatest potential impact.
Channels driving conversions
Rank your data, identify the largest contributors, and focus improvement work where it has the greatest potential impact.
Inventory items driving movement
Rank your data, identify the largest contributors, and focus improvement work where it has the greatest potential impact.
Frequently asked questions
What does an 80/20 calculator calculate?
It ranks your categories and calculates their individual and cumulative contribution so you can see how close your real data is to an 80/20 concentration.
Does every dataset follow 80/20?
No. 80/20 is a useful rule of thumb, not a universal mathematical law. Your data may show a different ratio.
What is the vital few?
The vital few are the relatively small number of categories that account for a large share of the total result.