More suitable Substitution Box Can anyone suggest me any fast searching method or algorithm to find best S-Box among a big number of S-boxes? For example; if I have 100 different S-boxes, I want to pick that one which is more secure than the others.
There is no such specific algorithm to find the best S-box but you can construct a Diference Distribution Table(DDT) like this and check out the values in it .A DDT is a matrix containing input differences as rows and corresponding output differences in column.

A better S-box has-
1- Lower values in its DDT
2- Less occurence of higher or highest value