Keyword use in document title
Global link popularity of web site
Link texts of inbound links
Keyword use in body text
Age of web site
Keyword use in H1 headline texts
Keyword use in domain name
Keyword use in page URL
Links from social networks
Server speed
Keyword use in H2-H6 headline texts
Keyword use in IMG ALT attributes
Top level domain of web site
Keyword use in bold body text
Number of visitors to the site
Keyword use in same site link texts
Keyword use in outbound link texts
Keyword use in same site link URLs
Keyword use in outbound link URLs
Keyword use in meta description
Number of trailing slashes in URL
HTML validation of web page to W3C standards
Readability level of web page
Keyword use in meta keywords
Keyword use in the first sentence of the body text
Keyword use in HTML comments
Search engine compatibility
Factors that could prevent your top ranking
Table: Number of keywords
Table: Keyword density
Table: Keyword position
Table: Number of words
Table: Number of characters
Table: Ranking factors digest