imgs = document.getElementsByTagName("img") console.log(imgs); for (let i = 0; i < imgs.length; i++) { img = imgs[i]; if(img.src.includes("/thumb/")) { pars_link = img.src.split("/").reverse(); file_name = pars_link[0]; pars_link[0] = file_name.replace("_b", ""); ref_res = pars_link.reverse().join("/"); console.log(ref_res); img.setAttribute('data-src', ref_res); img.setAttribute('src', ref_res); console.log(img); }; }