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Correlation Coefficient Calculator

Compute the Pearson correlation coefficient (r) between two variables from paired summary statistics — n, Σxy, Σx, Σy — to measure how strongly they move together linearly. The number ranges from −1 (perfect negative linear relationship) through 0 (no linear relationship) to +1 (perfect positive linear relationship).

Number of Pairs

Sum of XY

Sum of X

Sum of Y

Sum of X²

Sum of Y²

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Statistics

Standard Deviation Calculator

Compute the sample standard deviation directly from three summary statistics — sample size n, the sum of values Σx, and the sum of squared values Σx². This is the spread metric used in virtually every empirical study, quality-control chart, and risk model.

Sample Size

Sum of Values

Sum of Squares

Fill in the required fields to see your result.

Key differences

	Correlation Coefficient Calculator	Standard Deviation Calculator
Category	Statistics	Statistics
Inputs required	6	3
Result	Correlation Coefficient	Standard Deviation
What it does	Compute the Pearson correlation coefficient (r) between two variables from paired summary statistics — n, Σxy, Σx, Σy — to measure how strongly they move together linearly. The number ranges from −1 (perfect negative linear relationship) through 0 (no linear relationship) to +1 (perfect positive linear relationship).	Compute the sample standard deviation directly from three summary statistics — sample size n, the sum of values Σx, and the sum of squared values Σx². This is the spread metric used in virtually every empirical study, quality-control chart, and risk model.