---
title: "Correlation Calculator — Pearson r, Spearman ρ, R², Linear Regression"
description: "Calculate Pearson correlation coefficient (r), Spearman's rank correlation (ρ), R², and linear regression line from paired data. Used in AP Statistics, A-Level, IB Math, psychology and social science research."
url: "https://worldcalculators.org/calculators/correlation/"
canonical: "https://worldcalculators.org/calculators/correlation/"
---

# Correlation Calculator

Calculate Pearson correlation coefficient (r), Spearman's rank correlation (ρ), R², and linear regression line from paired data. Used in AP Statistics, A-Level, IB Math, psychology and social science research.

## Quick answer

US AP Statistics: covers Pearson r, scatterplots, LSRL (least squares regression line), and residual plots. UK A-Level Psychology: Spearman's rho is typically taught alongside Pearson r, given psychology's use of ordinal data. IB Mathematics AA HL: regression and correlation including Pearson's product-moment correlation coefficient and significance testing. Germany Abitur: regression (lineare Regression) is a standard component of the probability and statistics section. Social sciences globally: Spearman ρ and Kendall's tau dominate when data is ordinal.

## Frequently Asked Questions

US AP Statistics: covers Pearson r, scatterplots, LSRL (least squares regression line), and residual plots. UK A-Level Psychology: Spearman's rho is typically taught alongside Pearson r, given psychology's use of ordinal data. IB Mathematics AA HL: regression and correlation including Pearson's product-moment correlation coefficient and significance testing. Germany Abitur: regression (lineare Regression) is a standard component of the probability and statistics section. Social sciences globally: Spearman ρ and Kendall's tau dominate when data is ordinal.
No — this is one of the most important lessons in statistics worldwide. A strong correlation between X and Y could mean: X causes Y, Y causes X, a third variable Z causes both, or it's a spurious correlation (coincidence). Famous examples: ice cream sales correlate with drowning rates (both caused by summer heat). Shoe size correlates with reading ability in children (both caused by age). Establishing causation requires: controlled experiments with randomisation, intervention studies, or causal inference methods (Granger causality, instrumental variables).

Source: https://worldcalculators.org/calculators/correlation/
Markdown mirror of the HTML page. Prefer this URL for RAG; the interactive calculator still lives on the HTML page.