end

Returns the offset of the character immediately following the end of the nth element of the match array in the string. n can be a string or symbol to reference a named capture.

m = /(.)(.)(\d+)(\d)/.match("THX1138.")
m.end(0)         #=> 7
m.end(2)         #=> 3

m = /(?<foo>.)(.)(?<bar>.)/.match("hoge")
p m.end(:foo)    #=> 1
p m.end(:bar)    #=> 3