Random Number Game, Trouble with Min and Max

I'm trying to write a random number game in JavaScript, but I'm having a lot of trouble with getting the random number to actually generate something in between min and max if they're changed.

This is what I have so far:

var min = 1,
    max = 10;

function randomNumber() {
    var val;
    do {
        val = Math.round(Math.random() * max);
    } while (val<=(min - 0.5));
    return val;
}

However, if I change min and max, the numbers just don't really work out.

I'd appreciate any help, thanks.