Bash comparison between strings - equal but not equal for it

I just wanted to do a really simple comparison between 2 strings in Bash :

stat=`curl -Is $url | head -n 1` 
echo $stat
if [ "$stat" = "HTTP/1.1 200 OK" ];then
    echo "$symbol is OK"
    echo $stat
    valide=$(( $valide + 1 ))
else
    echo "$symbol is 404"
    echo $stat
    err=$(( $err + 1 ))
fi

But even if "stat" is completely the same, the result stay that it does not equal :

HTTP/1.1 200 OK
AAA is 404
HTTP/1.1 200 OK

How can i modify my code ?

I had also a lot of errors with "/" ("unexpected operator", ...) in the string before arrive to this code sample, and i tried many different approaches like contains ("200") with the same result.

Thank you in advance !