Google ranking factors

All state­ments about Google’s search algorithm are based on hints given by Google employees in in­ter­views and press releases. They have also been verified by cross­check­ing patent ap­pli­ca­tions as well as empirical ob­ser­va­tions. Nev­er­the­less, the following points aren’t of­fi­cial­ly confirmed. The following ranking factors have proven them­selves in daily practice; websites optimized for these criteria generally obtain a good position in the organic search results.

Keywords in URLs

If a keyword is included in a URL, it lets the search engine know that the site has a certain relevance to the search query. URLs con­tain­ing keywords are often as­so­ci­at­ed with good Google rankings, although in recent years, keyword domains or sub­do­mains have become less important. Some SEO experts suggest a con­nec­tion between the word order in the URL and the ranking. They claim the main keyword is more sig­nif­i­cant if it’s at the beginning of the URL, but repeating the keyword should be avoided at all costs. Re­gard­less of the ranking, keyword domains also have the advantage that the relevant search terms can be high­light­ed in bold in the search results list.

Keyword in the title tag

Placing relevant search terms in the title tag of an HTML page is even more important than the keyword in the URL. This tag defines the title of a website and counts as an important content element. Equally important is the relevance signal that is sent out by the main keyword in the title tag; it’s theorized that a prominent position at the beginning of the title sends out a stronger relevance signal and therefore has a positive influence on the ranking. Keywords in website titles are presented in bold in the SERPs.

Keyword density

Due to the risk of ma­nip­u­la­tion, Google doesn’t attribute much im­por­tance to keyword density as it used to. Despite this, keywords still serve to convey the topic of a website to the search engine. The absolute frequency of relevant search terms in a text is not as important as how relevant the keyword is. Googles uses the TF-IDF (term frequency-inverse document frequency) of a website, in other words, the keyword density in relation to the inverse document frequency. The latent semantic indexing (LSI) is also used; this forms a thematic cloud of related words from the main keyword. In order to rank highly, a text should not only contain the specified keyword, but also synonyms for it. If the text does contain relevant synonyms, it sends out a stronger relevance signal.

Keyword emphasis

If keywords in a text are em­pha­sized with HTML markups, it signals to the search engine that these words are es­pe­cial­ly important to the text. A text con­tain­ing relevant search terms is clas­si­fied as relevant during the web search and will therefore rank higher. Keywords or keyword phrases can be made to stand out from the rest of the text through bolding, ital­i­ciz­ing, un­der­lin­ing, and font size.

Keywords in titles

A special case regarding keyword emphasis is the placing of relevant search terms in the HTML main header (H1) and in the sub headings (H2 and H3). Google rates keywords in these struc­tur­al elements very highly since they act as relevance signals and fa­cil­i­tate the un­der­stand­ing of the website content

Keyword stemming

Google reduces variants of a search term into one col­lec­tive word stem. SERPs take into account sites that contain keywords in different gram­mat­i­cal forms as well as websites with exact match keywords. It can be assumed, on the contrary, that texts ex­clu­sive­ly con­tain­ing exact match keywords may not rank as well since con­ju­gat­ing search terms is part of the natural creation process of texts.

Keyword in alt attribute

The Google crawler might be effective at in­ter­pret­ing texts, but its un­der­stand­ing of image elements isn’t so great. The in­for­ma­tion has to be written in the HTML code in order to convey to the crawler what an image displays and whether it has anything to do with the thematic context of the website content. To achieve a good ranking you should include all essential in­for­ma­tion in the file, the title, and in the image caption, as well as in the alt attribute. Lastly, don’t forget the de­scrip­tion of the image, which will be shown as al­ter­na­tive text in case an error prevents the image from being shown.

Mul­ti­me­dia content

Google ranks mul­ti­me­dia elements such as images and videos much higher since they are more in­ter­est­ing for the visitor. Placing in­for­ma­tion on different channels offers more value to users and so these websites appear higher in the SERPs.

Read­abil­i­ty

What’s known for certain is that Google analyzes the com­pre­hen­si­bil­i­ty of texts on websites. Whether this in­for­ma­tion flows into the algorithm for the website or how it’s evaluated remains to be seen. On the one hand, texts with smaller read requests and a lower reading level can have a positive influence on the search engine ranking since they are un­der­stand­able for a wider audience. On the other hand, a higher reading level is a quality feature. The read­abil­i­ty index can help to dif­fer­en­ti­ate filler texts from high-quality content. To make the site as user-friendly as possible, website owners should ensure that the content is readable. Texts that are for­mu­lat­ed with the target group in mind increase the retention time on the website, a factor that has been proven to influence the ranking. You can find practical text analysis tools here: http://www.online-utility.org/text/analyzer.jsp

High-quality outbound links

Links that lead from one site to another are known as outbound links. Web crawlers are pro­grammed to follow these links. If the links from your website lead to high-quality sites, they can pos­i­tive­ly influence the ranking of that site. Outbound links also helps the web crawler to determine the site’s theme. It’s important not to include too many as they can distract from the main content. You should also regularly check the links to make sure none of them are dead. If any lead to a dead end, there’s more chance of Google seeing the site as outdated and de­val­u­at­ing it.

Inbound links

Unlike outbound links, inbound links (also called backlinks) are links that lead from other websites to yours. SEO experts have suggested a possible cor­re­la­tion between a site’s inbound links and its ranking in the organic search results. This as­sump­tion is supported by the fact that a no­tice­able amount of websites with high-quality backlink profiles can be found on the top spots in the SERPs. Pro­fes­sion­al search engine op­ti­miza­tion places great sig­nif­i­cance on improving a website’s backlink structure. A high link pop­u­lar­i­ty has, in most cases, a positive influence on the Google ranking.