LOCAL DATA ANALYSIS

Pearson correlation calculator

Calculate Pearson correlation from paired values, view a scatter plot and export the result. Supports explicit decimal comma or decimal point input.

Formula and method

r = Σ[(x − mean X)(y − mean Y)] ÷ √[Σ(x − mean X)² × Σ(y − mean Y)²]

Pearson correlation measures linear association between two numeric variables. Its coefficient ranges from −1 to +1; the sign describes direction and the magnitude describes linear alignment.

Worked example

For X = 10, 20, 30, 40, 50 and Y = 21, 29, 33, 41, 46, Pearson r is approximately 0.9953. These values are illustrative paired observations.

What the result can tell you

At least two pairs and variation in both variables are needed. Small samples, outliers and nonlinear patterns need attention. Correlation does not establish causation. This tool returns a descriptive coefficient, not a significance test or confidence interval.

Method reference: NIST: correlation.

Continue with a chart