Which web page elements lead to high Google rankings?

A Recent study was done by a German company, Sistrix, where they analyzed web page elements of top ranked pages within Google to find out which elements lead to high Google rankings. According to the study, they analyzed 10,000 random keywords, and for every keyword, they analyzed the top 100 Google search results.

Sistrix (I translated the site for you into English here) analyzed the influence of the following web page elements: web page title, web page body, headline tags, bold and strong tags, image file names, images alt text, domain name, path, parameters, file size, inbound links and PageRank.

These are some of the results they compiled:

Keywords in the title tag seem to be important for high rankings on Google. It is also important that the targeted keywords are mentioned in the body tag, although the title tag seems to be more important.
Keywords in H2-H6 headline tags seem to have an influence on the rankings while keywords in H1 headline tags don’t seem to have an effect.
Using keywords in bold or strong tags seems to have a slight effect on the top rankings. Web pages that used the keywords in image file names often had higher rankings. The same seems to be true for keywords in image alt attributes.
Websites that use the targeted keyword in the domain name often had high rankings. It might be that these sites get many inbound links with the domain name as the link text.
Keywords in the file path don’t seem to have a positive effect on the Google rankings of the analyzed web sites. Web pages that use very few parameters in the URL (?id=123, etc.) or no parameters at all tend to get higher rankings than URLs that contain many parameters.
The file size doesn’t seem to influence the ranking of a web page on Google although smaller sites tend to have slightly higher rankings.
The number of inbound links and the PageRank has a large influence on the page rankings on Google. The top result on Google has usually about four times as many links as result number 11.

I agree with almost all of the aspects above, but here are some general comments I’d like to mention:
As I’ve previously blogged, the Title tag is THE most important element in any website. Placing your keywords in the Title should follow automatically. All Title tags should be optimized to contain your main keyword or keyword phrase.

With regards to H2-H6 header tags having a higher prominence than H1 tags, I found it to be the other way around and always thought that H1’s have more weight.

If you remember the SEOmoz “Google Search Engine Ranking factors” study, then you’ll understand my reasoning.

Suffice it to say that Header tags do carry weight in page rankings and it certainly out-weighs having keywords in bold tags and keywords in image file names and Alt attributes.

I do not fully agree that the PageRank of a site has much affect on the site rank as PR is calculated from many factors including many of these mentioned above. I’ve seen many websites with a lesser PageRank ourtank a page with a higher PageRank.

With the exception of PageRank affecting your rank for certain keywords in the SERP’s, I’d say all of the above play a role in how your site performs, so it is best you make sure you have all of them optimized on your website.

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