Statistics

Covariance Calculator

How two variables move together, before standardising.

Enter your values

ⓘ Live results

Results
Sample covariance
13.5
Population covariance
10.8
Correlation r
0.98722
Direction
Positive — they rise together
Mean of X / Y
6 / 8.8
Sum of products
54

Quick answer

Covariance measures whether two variables move together: positive means they rise together, negative means one falls as the other rises.

cov = Σ(xᵢ − x̄)(yᵢ − ȳ) ÷ (n − 1)

How to use the Covariance Calculator

  1. 1Enter the X values in order.
  2. 2Enter the matching Y values.
  3. 3Read covariance for direction and correlation for strength on a −1 to +1 scale.

Worked example

Using the values the calculator loads with:

Inputs

  • X values2, 4, 6, 8, 10
  • Y values3, 7, 8, 12, 14

Results

  • Sample covariance13.5
  • Population covariance10.8
  • Correlation r0.98722
  • DirectionPositive — they rise together
  • Mean of X / Y6 / 8.8
  • Sum of products54

Frequently asked questions

Why is covariance hard to interpret?

Its size depends on the units — change metres to centimetres and covariance jumps 100-fold. Correlation fixes that.

Does zero covariance mean independence?

Not necessarily. It rules out a linear relationship, but a perfect U-shape can still have zero covariance.

About this calculator

Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.