Skip to content

Correlation and regression

Pearson or Spearman with a confidence interval on r, plus a fitted line.

Runs in your browser
Read in your browser. The file is not uploaded.
Method

Pearson — assumes a straight-line relationship and roughly normal data.

Paste at least three paired values into each column.

Formular = Σ(x−x̄)(y−ȳ) ÷ √(Σ(x−x̄)²Σ(y−ȳ)²); CI via atanh(r) ± z·(n−3)^−½
ModelPearson
  • Fisher’s z transformation for intervals on r — Metron, 1921

Calculated in your browser. Nothing you entered was sent anywhere.

Plot the data before trusting any of this. Anscombe’s quartet is four datasets with identical correlation coefficients and entirely different shapes.

About this tool

Correlate two variables and fit a straight line through them. Reports r with its confidence interval — the part most calculators omit, and the part that distinguishes r = 0.6 from eight points from r = 0.6 from eight hundred.

Related tools

  • t-test calculator — Compare two groups and get the effect size and interval, not just a p-value.
  • One-way ANOVA — Compare three or more groups, with variance explained and every pair tested.

Science last reviewed .