Which method is faster to select body element? [duplicate]

Question

What is better to use for performance in JavaScript?

document.children[0].children[1]

vs

document.querySelector('body')

Which is more faster in performance?

Answer 1

Here you've the result from fast to slow:

1. document.body (by far)
2. document.querySelector('body'), document.children[0].children[1], document.getElementsByTagName('body')[0] (about the same)
3. document.querySelectorAll("body")[0], $('body')

Source JSBench (try it yourself)