Home / Matthews Correlation Coefficient Calculator

Matthews Correlation Coefficient Calculator

Matthews Correlation Coefficient Calculator helps with statistics, diagnostics and similarity scores. Use True positives, True negatives, False positives, False negatives to estimate MCC rather than relying on a fixed rule of thumb. This calculator uses the relationship (tp*tn-fp*fn)/sqrt((tp+fp)*(tp+fn)*(tn+fp)*(tn+fn)). The coefficient is undefined if any marginal product is zero. It runs locally in your browser, so the values can be changed to explore a different scenario without transmitting the entered numbers to an external calculation service.

How to use this calculator

  1. Check the measurements for True positives, True negatives, False positives, False negatives. Each field displays its input unit; do not mix cm, m, seconds or minutes.
  2. Enter the quantities for your own statistics, diagnostics and similarity scores scenario. Use ungrouped numeric values, with a period for decimals.
  3. Read the result in MCC and compare the underlying formula with your real situation. The coefficient is undefined if any marginal product is zero.

How the Matthews Correlation Coefficient Calculator works

Result in MCC = (tp*tn-fp*fn)/sqrt((tp+fp)*(tp+fn)*(tn+fp)*(tn+fn)). Inputs are expressed in the units shown in their labels.

  • The output uses the current values of True positives, True negatives, False positives, False negatives, with no live service data, manufacturer information or personal information. This is a model, not a real-time measurement.
  • The tool rejects values that violate the relevant input relationship or make the expression undefined. The coefficient is undefined if any marginal product is zero. Review quantities, precision and units before using the result for a purchase, plan or technical choice.

Worked examples

Worked example: Matthews Correlation Coefficient Calculator

Suppose True positives = 70, True negatives = 85, False positives = 15, False negatives = 30. The calculator processes these numeric quantities using its defined relationship.

Apply (tp*tn-fp*fn)/sqrt((tp+fp)*(tp+fn)*(tn+fp)*(tn+fn)) to those inputs, preserving the unit conversions in the expression.

Calculated value: approximately 0.5562939 MCC.

Understanding the result

The default example gives approximately 0.5562939 MCC; this is a mathematical output based on the example inputs, not a forecast of actual observed conditions.

The coefficient is undefined if any marginal product is zero.

Important notes

The coefficient is undefined if any marginal product is zero.

For a production decision, check the source measurements and local requirements before trusting this MCC estimate. The tool rejects values that violate the relevant input relationship or make the expression undefined.

Frequently asked questions

What is the Matthews Correlation Coefficient Calculator used for?

It converts True positives, True negatives, False positives, False negatives into a calculated quantity in MCC, using the formula displayed above.

What assumptions matter for this calculator?

The coefficient is undefined if any marginal product is zero. The outcome changes when measurements, operating conditions or units differ.

How do I verify a result from the Matthews Correlation Coefficient Calculator?

Recalculate the worked example independently, check your units, and use measured data when available. The tool rejects values that violate the relevant input relationship or make the expression undefined.

Related calculators

  • Percentage Calculator — Calculate percentages, percentage of a number, and percentage change between two values.
  • Number Base Converter — Convert numbers between binary, decimal, hexadecimal, and octal.
  • Fraction Calculator — Add, subtract, multiply, and divide fractions with step-by-step simplification.
  • LCM & GCD Calculator — Find the Least Common Multiple and Greatest Common Divisor of any set of numbers.
  • Roman Numeral Converter — Convert numbers to Roman numerals and Roman numerals back to numbers.
  • Prime Number Checker — Check if a number is prime, and find all prime numbers up to any limit.

This page provides a calculation tool plus explanatory information so you can understand what the result means and when the underlying method may not fit your situation.