The coefficient of determination R2 tells at what extent the given data fits the line or curve. It even decides the proportion of variance of one variable to the other. The R2 value lies between 0 and 1.
The R Square Calculator is a online tool to calculate the value of R Square. You just have to enter the value of X score and Y score and the R square value instantly.
Lets see the steps to calculate R Square:
Step 1 :
Read the problem and take down the value of X score and Y score

Step 2 : Using X score and Y score. Find XY, X2 and Y2 then create a table out of it. Calculate $\sum$ X, $\sum$ Y, $\sum$ XY, $\sum$ X2, $\sum$ Y2.

Step 3 :To calculate correlation use the formula
R=$\frac{n \sum{XY} - \sum{X} \sum{Y}}{\sqrt{[N \sum X^2 - (\sum X)^2][N \sum Y^2 -(\sum Y)^2]}}$
Now calculate R2 to find the coefficient of determination.