可能浏览器设置的字体大小不一样
比如
<html>
<head>
<title>newpage</title>
<script defer>
alert(div1.style.pixelHeight);
alert(div1.offsetHeight);
</script>
</head>
<body>
<div name=div1 id=div1 style="height:18px">
<font size=10>12321412412421412</font>
</div>
</body>
</html>
比如
<html>
<head>
<title>newpage</title>
<script defer>
alert(div1.style.pixelHeight);
alert(div1.offsetHeight);
</script>
</head>
<body>
<div name=div1 id=div1 style="height:18px">
<font size=10>12321412412421412</font>
</div>
</body>
</html>
比如
<html>
<head>
<title>newpage</title>
<script defer>
alert(div1.style.pixelHeight);
alert(div1.offsetHeight);
</script>
</head>
<body>
<div name=div1 id=div1 style="height:18px">
<font size=10>12321412412421412</font>
</div>
</body>
</html>
还有其他原因吗?