Correlation Coefficient Calculator

Correlation guide

Read Pearson correlation as linear association, not proof of cause

Pearson r compares paired x-y observations and returns a value from -1 to 1. Values near 1 suggest a positive linear relationship, values near -1 suggest a negative linear relationship, and values near 0 suggest little linear association in the entered pairs.

A strong correlation can still be misleading when the sample is tiny, the relationship is curved, outliers dominate the result, or both variables move because of another factor. Plot the pairs, check units, and keep correlation separate from causation.

  • Use matched x-y pairs from the same observation.
  • Check for outliers before trusting r.
  • Use domain knowledge before inferring cause.

Statistics guide

How to use the Correlation Coefficient Calculator

Calculate Pearson correlation from five x-y data pairs. The page also explains the pearson correlation and shows a practical example: Five x-y pairs can show positive, negative, or weak linear association.

  1. 1

    Enter your details

    Enter five x-y data pairs, then complete any other fields shown in the calculator.

  2. 2

    Check the calculation

    Review the result alongside the pearson correlation: r = sum((x - mean x)(y - mean y)) / sqrt(sum(x - mean x)^2 sum(y - mean y)^2).

  3. 3

    Compare scenarios

    Change one or more inputs to see how they affect the correlation Coefficient Calculator result before you use the estimate.