/*This function will load script and call the callback once the script has loaded*/ function loadScriptAsync(scriptSrc, callback) { if (typeof callback !== 'function') { throw new Error('Not a valid callback for async script load'); } var script = document.createElement('script'); script.onload = callback; script.src = scriptSrc; document.head.appendChild(script); } /* This is the part where you call the above defined function and "calls back" your code which gets executed after the script has loaded */ loadScriptAsync('https://www.googletagmanager.com/gtag/js?id=G-270567787', function () { window.dataLayer = window.dataLayer || []; function gtag() { dataLayer.push(arguments); } gtag('js', new Date()); gtag('config', 'G-270567787', { 'anonymize_ip': true }); })