set width and height of div javascript code example

Example 1: javascript get element width

var width = document.getElementById('myID').offsetWidth;//includes margin,border,padding
var height = document.getElementById('myID'). offsetHeight;//includes margin,border,padding

Example 2: javascript set div height

document.getElementById("myBtn").style.height = "50px";

Example 3: javascript set element width

document.getElementById("myElID").style.width = "100px";