JAVASCRIPT

javascript get element width

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

get element size javascript

// Get Content + Padding + Border
let box = document.querySelector('div');
let width = box.offsetWidth;
let height = box.offsetHeight;

// Get Content + Padding only
let box = document.querySelector('div');
let width = box.clientWidth;
let height = box.clientHeight;