Is Keyword Density part of on-page optimization in terms of using h1tag, meta tags and so on.. Should it be listed in that list?
Yes. It is more important in content. H1 tag KD should be short and to the point. No particular order here. It's just the percentage of the density that counts. Don't over do it, compare it with your competitors.
SolomonZhang is right, it is part of the on-page optimization. Just make sure your keywords should be place from middle up to the top of the content. So that your density and prominence would be in the right numbers.
Go to any search engine. Type in your primary keyphrase. Look at the results that fall into the number one through five slots. Some have higher levels, some have lower levels.
Go to any search engine. Type in your primary keyphrase. Look at the results that fall into the number one through five slots. Do they all have the same keyword density? No. Some have higher levels, some have lower levels.
Keyword density is part of on-page optimization. It's an important factor to know if a page is relevant to a certain keyword or key phrase by looking at the percentage of keywords used within the page
keyword density is very important. if done right, it can work to your advantage. however, u don't wanna over do it as it will be considered an spam by SEs. i suggest u look for other sites with your keyword and get few from the top. then analyze their keyword density. ig you sample 5 sites, then take an average of all the site's keyword density which should be a safe number for you. you can use http://keyworddensity.com/ to see which site has what % of density based on a specific keyword.