About the Correlation Coefficient Calculator

The Pearson correlation coefficient (r) measures the strength and direction of a linear relationship between two variables, ranging from −1 to +1. It is computed by normalizing the covariance of the two series by the product of their standard deviations.

Interpreting the Result

|r| ≥ 0.8 is a very strong relationship, 0.6–0.8 strong, 0.4–0.6 moderate, 0.2–0.4 weak, and below 0.2 very weak. The sign shows direction — positive means both move together, negative means they move in opposite directions.