javascript各種はブラウザの幅と高さの関数を得ます.

function getInfo()
{
    var s = "";
    s += "        ："+ document.body.clientWidth+"
";
    s += "        ："+ document.body.clientHeight+"
";
    s += "        ："+ document.body.offsetWidth + " (          )"+"
";
    s += "        ："+ document.body.offsetHeight + " (      )"+"
";
    s += "        ："+ document.body.scrollWidth+"
";
    s += "        ："+ document.body.scrollHeight+"
";
    s += "        (ff)："+ document.body.scrollTop+"
";
    s += "        (ie)："+ document.documentElement.scrollTop+"
";   
    s += "        ："+ document.body.scrollLeft+"
";
    s += "        ："+ window.screenTop+"
";
    s += "        ："+ window.screenLeft+"
";     
    s += "        ："+ window.screen.height+"
";
    s += "        ："+ window.screen.width+"
";
    s += "          ："+ window.screen.availHeight+"
";
    s += "          ："+ window.screen.availWidth+"
";
    s += "         "+ window.screen.colorDepth +"    "+"
";
    s += "        "+ window.screen.deviceXDPI +"   /  "+"
";
    s += " window           (ff) "+window.innerHeight+"
";   
    alert (s);
}