const tagSet = Array.from(document.querySelectorAll('*')) .map(item => item.tagName) .reduce((res, item) => { if (res[item]) { res[item] = res[item] + 1; } else { res[item] = 1; } return res; }, {}); const res = Object.keys(tagSet).map(item => ({ key: item, value: tagSet[item] })).sort((a, b) => b.value - a.value) console.log(res);


