2013 ranking factors update
Recommended link: Moz SEO Ranking factors 2013 edition
Many SEOs everywhere have now been following the SEOmoz (now Moz) ranking factors for a very long time - I think I start recommending them in training in 2005, can that be right?!
Over time the analysis has become more complex with a move from trusted experts' opinion to additional correlation based analysis. In many ways I prefer the original breakdown of on and off page factors for its simplicity - as shown below, but there are many more factors to consider now of course.
The best overall summary on ranking factors for non specialists is, for me, still the Experts' analysis.
This shows, according to Moz, that
Links are still believed to be the most important part of the algorithm (approximately 40%).
Keyword usage on the page is still fundamental, and other than links is thought to be the most important type of factor.
SEOs do not think social factors are important in the 2013 algorithm (only 7%), in contrast to the high correlations.
Since it's important for SEOs to look into the future so that their SEO, content and social media activity supports their future ranking I thought this summary of opinion was also useful, it shows the need to focus on these factors which we have covered on Smart Insights including Google+ authorship, perceived value (the long click referenced in our mobile SEO factors summary) and structured data.
The main SEO ranking factors - 2007 style
I have retained this summary from previous versions of this post since it can help newbies understand the SEO ranking factors better. I have used the summary below of the main on and off-page SEO factors based on v2 ranking factors report on my training courses and books for a long time since they give a one page snapshot. I continue to do so before showing the newer data since it shows the relative importance of factors like the title tag well and the relative unimportance of the meta keywords...
- <title> tag = 4.9/5
- Keyword frequency and density = 3.7/5
- Keyword in headings = <h1> = 3.1, <h2> = 2.8
- Keyword in document name = 2.8
- Meta name description = 2/5
- Meta name keywords = 1/5
This is useful to highlight the myth of the importance of meta tag which so many generalist marketers seem to cling to... I would rate the meta name factors even lower.
- Link anchor text contains keyword = 4.4/5
- More backlinks (higher PageRank)= 4/5
- Link Popularity within the Site's Internal Link Structure=4/5
- Page assessed as a hub = 3.5/5
- Page assessed as an authority = 3.5/5
- Link velocity (rate at which changes) = 3.5/5
This Slideshare presentation from Mozcon is a good way to browse the latest correlations covering specific such as the type of anchor text which is most effective in ranking.