I don't know what you're measuring (onload?), but it's not giving you enough precision to make a conclusion about the performance of the HTML parser. If you pr

I don't know what you're measuring (onload?), but it's not giving you enough precision to make a conclusion about the performance of the HTML parser. If you profile the page w/ devtools Performance panel, you'll see that just 5% of the CPU cost used to load & render the page is spent parsing the HTML. At that level I'm seeing costs of 22-36ms per load. And, spoiler alert: after repeated runs I'm not seeing any substantial difference between these test pages. And based on how the HTML parser works, I wouldn't expect it. (I work on web performance on the Chrome team)