The border-spacing specifies the width between table cells. It can take either one or two values; these should be units of length.
Example
You can try to run the following code to set the width of table cells:
<html>
<head>
<style>
table.one {
border-collapse:separate;
width:300px;
border-spacing:15px 40px;
}
</style>
</head>
<body>
<table class = "one" border = "2">
<caption>The border-spacing property</caption>
<tr><td> India </td></tr>
<tr><td> UK </td></tr>
</table>
<br />
</body>
</html>