You can easily find the p value corresponding to a X2 value with our . If you want to find the p value by using a table with critical X2 values, instructions are given below.

Finding $p$ value corresponding to $X^2$ value, using the table with critical $X^2$ values

Assuming a table with a row per degrees of freedom and a column per upper tail probability

$p$ value is the probability of finding the observed $X^2$ value or larger, given that the null hypothesis is true.
  1. Find the row with the appropriate number of degrees of freedom (df)
  2. Search for the two $X^2$ values in this row, that enclose the $X^2$ value you found
  3. Find the upper tail probabilities corresponding to these two $X^2$ values. You can find them at the top of each column. The $p$ value corresponding to the $X^2$ value you found is between these two values
p value given chi squared value