Метрика

 //вставлять перед закрывающимся тегом </body> пример ключа ?yk=45421101
   <script>
function setUrlParamsToLink() {
    if (window.location.search.substring(1)) {
        let url = window.location.search.substring(1).split('&');
        let urlParams = {};
        var urlPid, urlLid;
        url.forEach(function (entry) {
            urlParams[entry.split('=')[0]] = entry.split('=')[1];
        });
        var GetUrlValue = urlParams['yk'];
        if(urlParams['yk']){
                document.write(' <script type="text/javascript" > (function (d, w, c) { (w[c] = w[c] || []).push(function() { try { w.yaCounter'+GetUrlValue+' = new Ya.Metrika({ id:'+GetUrlValue+', clickmap:true, trackLinks:true, accurateTrackBounce:true, webvisor:true, ut:"noindex" }); } catch(e) { } }); var n = d.getElementsByTagName("script")[0], s = d.createElement("script"), f = function () { n.parentNode.insertBefore(s, n); }; s.type = "text/javascript"; s.async = true; s.src = "https://mc.yandex.ru/metrika/watch.js"; if (w.opera == "[object Opera]") { d.addEventListener("DOMContentLoaded", f, false); } else { f(); } })(document, window, "yandex_metrika_callbacks");</scr'+'ipt> ');
        }
            else{
        console.log("Введите параметр yk");
                }

    }

}
setUrlParamsToLink();
</script>