Tryit Editor v1.8

Source Code:
<!DOCTYPE html> <html> <head> <script src="../../ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"> </script> <script> $(document).ready(function(){ $("#btn1").click(function(){ $("div").width(500); }); $("#btn2").click(function(){ $("div").width("10em"); }); $("#btn3").click(function(){ $("div").width("300pt"); }); }); </script> </head> <body> <button id="btn1">Set width of div to 500px</button> <button id="btn2">Set width of div to 10em</button> <button id="btn3">Set width of div to 300pt</button> <p><b>Note:</b> Use "" for em, pt, etc.</p> <div style="height:100px;width:300px;border:1px solid blue;background-color:lightblue;"></div><br> </body> </html>
Result:
W3Schools.com - Try it yourself