A complete list of Google ranking factors
According to statistics, more than one billion people use Google search, thus generating about 115 billion of unique monthly searches. Besides this, Google makes up for 67.7% on the search engine market, making marketing experts, eager to have their sites positioned high in SERP, work even harder on completing as many demands Google makes.
Google algorithm is highly sophisticated and covers many parameters, which makes it harder for the experts to know with certainty what is better for ranking individual pages on the Internet. Although Google never published the official list of all SEO ranking factors, it was officially confirmed that there is around 200 signals based on which a rank is decided upon in the search engine’s results page.
For better convenience and organization, SEO ranking factors have been divided into categories, such as domain factors, on-page and on-site factors, backlink factors, user interaction, special algorithm rules, social signals, brand signals, on-site and off-site web spam factors. Browse through each category and read about them in greater detail.
Domain age - a factor that influences ranking, but not to such great extent.
Keyword in domain name - does not cause such great effects as expected, but is still a relevant signal.
Keyword as the first word in domain - according to the existing statistics, domains starting with a target keyword are in advantage of sites without one, with one in the middle or at the end of domain name.
Domain registration length - domain expiration date can be used as its legitimacy prediction factor. According to Google, legitimate domains are often paid for many years upfront, whereas other are reserved usually for a year.
Keyword in subdomain name - the occurrence of a keyword in subdomain title can influence ranking positively.
Domain history - a site with authorship infringement or with recurring drops can make Google check its history and give it negative points.
Exact Match domain - includes all domains that contain a targeted keyword. In October 2012, Google announced EMD update, a new filter which prevents low quality websites from ranking good just because they contain a keyword in their domain name. If a site is of high quality, there are no obstacles for it to rank good. After this change in the algorithm, Google started preferring branded domains (domains which contain the name of a brand) as a good starting point for authority establishment.
Public and private WhoIs data - domain data from Whois sites should not be hidden. Google recommends that they be publicly available and match those on your site. If you hide or write different data – this may look a bit suspicious.
Penalized Whois owner - if Google sees that someone is spamming, it is logical for them to examine other sites owned by the spam marked person.
Country-code TLD extensions - if you have a country code TLD (top level domain), such as .uk, .es, .de, .rs – this can improve site’s ranking in your target country but, at the same time, limit the opportunity for global ranking as well.
Keyword in page title - besides page content, title tag is the second most important ranking signal. Learn how to improve content quality, including writing great headlines for great SEO.
Title tag starting with a keyword - according to Moz.com, title tag which starts with keywords performs better than title tags ending with a keyword.
Keyword in description tag - another signal which does not influence ranking that much is meta tag description, but it still makes a difference if used properly. If you have a sensible description tag with keywords, the odds are that users will find you via SERP.
Keyword in H1 tag - H1 is another relevance signal for Google. Make sure that H1 tag draws user’s attention to read page content. Tip: do not use more than one H1 tag per page.
Page keyword - if you want a website to rank good for a keyword, it needs to be used more frequently than other words on the page. This is a clear signal for Google that the page is relevant for a search result.
Content length - web pages with longer content are often ranked better than pages with shorter content. Content length is directly connected with positions in SERP. Of course, the only condition is that content is of good quality and relevance.
Keyword density - this factor serves for Google to detrmine the topic of the page. A keyword should not be repeated too much in the text; content should be as natural as possible and user-friendly. Frequent repetitions can lead to unwanted effects and Google penalty.
Keyword latent semantic indexing (LSI) - this SEO term signifies connected keywords or synonyms which appear in the text with the goal to better define the keyword. If one searches for a keyword ‘apple’, this term does not give out information about whether it is the fruit or the brand one is searching for. Based on LSI keywords within the text, search engines decide on a page’s relevance for a certain query.
LSI keywords in title and description tags - the aforementioned applies here as well – LSI keywords help Google differentiate between synonyms.
Page loading speed - one of Google’s ranking factors. Spiders can establish site speed based on a page’s code and file size.
Duplicate content - refers to content parts similar to or the same as on the rest of the domain itself or on some other domains. This can impact ranking very badly.
Canonical tag - an HTML tag which can prevent duplicate content emergence. As it often happens on dynamic sites, there are more versions of one and the same web page on different URL addresses. If you use canonical tag properly, you can avoid an unwanted penalty.
Loading speed in Google Chrome web browser - Google can also use data obtained from Chrome users in order to get a better insight into page loading speed. It takes into consideration signals such as server response speed, content delivery network (CDN), and the like.
Image optimization - images on the page are an important on-page signal since Google takes into consideration ranking parameters such as file title, alt text, title, and heading. You need to create as descriptive data possible to help browsers understand what kind of image it is and offer it in search results.
Content update intensity - after Google caffeine algorithm update was rolled out in 2009, which significantly improved the speed and manner of content indexing, content updates became a significant ranking factor, especially for time-based searches. It is clear that Google shows publication date in some posts so users, having in mind that data, could evaluate content relevance. This factor also covers content freshness on both new and existing pages.
Content update ratio - another freshness factor is the importance of changes made. It is more important to change and remove entire sections than replace just a few words.
Page update history - how often was the page updated during a time period, daily, weekly, annually or biannually? The frequency of page updates also plays an important role in freshness.
Keyword prominence - how often the keyword was used in the first 100 words on the page can be a significant relevance signal.
Keyword in H2 and H3 tags - having a keyword in H2 and H3 page subtitles is another ranking signal with questioning relevance.
Keyword word order - a keyword which appears as an exact match on a page will rank better than in combination with another key phrase in different order. Keyword research is what plays an important role here.
Outbound link quality - many an SEO expert consider that links coming from high-authority sites help in obtaining trust from Google.
Outbound link topic - search engines can use content from pages you link to as a signal of relevance. Outbound links help Google in understanding better the subject and general sense of the page.
Grammar and spelling (orthography) - this is another signal for quality content.
Content syndication - is page content original? If it is copied from other indexed pages, it will not rank well or it will end up in replacement index for duplicate content.
Useful resources - according to Google’s general guidelines, websites which list additional resources indicate that their pages are of good quality. An example of this type of content can be currency converters, interactive recipes, etc.
Number of external links - too great a number of ‘dofollow’ links can harm page ranking and its visibility during search.
Multimedia content - images, videos, and other multimedia content can be considered a content quality signal.
Number of internal links to the page - the number of internal links towards a page means that it is more important than other pages on the site.
Quality of internal links to the page - links coming from pages with higher authority and PR (PageRank) have more powerful and bigger effect than pages with weaker authority.
Broken links - if you have too many broken links to a page, this could mean that a site is unreliable and abandoned. This is another page quality factor listed in Google Guidelines.
Page readability level - it is still not quite clear how Google uses this factor. Nevertheless, according to SEO experts, readability level is a factor which leaves low-quality websites behind high-quality sites.
Affiliate links - links coming from your business partners will not harm your ranking but, if there are too many of them, Google can start considering your parameters in order to determine site quality.
HTML errors - if you have too many errors in HTML code, this can indicate that the site is of low quality. Many SEO experts believe that W3C validation is weak and insignificant quality signal.
Domain host authority - one and the same page will have different authority on different sites.
Page Rank (PR) - – this is not the most significant factor but, basically, pages with higher PageRank do better than pages with lower.
URL length - long URLs can influence search visibility in a negative way.
URL slug - a page closer to the homepage will be of higher authority.
Human editors - even though it has never been officially confirmed, Google has a patent-pending system which enables human editors to influence search results.
Page category - a page which is a part of a closely connected category should get more relevance than a page without or with weak connection to a category.
WordPress tags - tags are relevance signal for sites on this platform.
Keyword in URL - another important signal/factor.
URL strings - Google can read categories in URL strings which signalize what the page is about.
References and resources - if a page demands it, listing resources and references can signal quality.
Ordered vs unordered lists - ordered lists help readers get a clearer picture of content, making it friendlier. Google agrees that it may prefer listed content.
Sitemap page priority - page priority parameter which can be dedicated in XML sitemap can influence ranking.
Too many external links - according to Google quality guidelines, pages with too many links distract users from the main content, and this is bad for ranking.
Quantity of keywords the page is ranked for - if a page is ranked good for a few keywords, this can be a quality signal for Google.
Page age - even though Google prefers fresh content, older pages which are updated on a regular basis can top newer pages.
User-adjusted layout - pages with good element layout, design and user experience (UX) are another indicator of quality. Google always chooses the users.
Parked domains - Google’s algorithm update from 2011 had influenced parked domain visibility. This algorithm was intended for automated detection of parked domains.
Content usability - another ranking factor. Google can sometimes differentiate between useful and quality content.
Content with value and unique contribution - Google declared that it searches for sites which do not contribute to or give anything new or useful on the web, with special emphasis on affiliate sites.
Contact page - according to Google quality document, sites which give out a significant amount of information are considered more useful, especially if that data corresponds to Whois registry data.
Domain trust rank - represents site’s trust measured by a number of quality backlinks from highly trustworthy sites. This is a very important ranking factor.
Site architecture - a site with good architectural design and organization enables Google to establish it in a suitable niche.
Site updates - ranking is also influenced by frequency of site updates and new content management.
Number of site pages - a number of pages on a site is a weak authority signal, but this data can be useful for Google to differentiate between weak affiliate sites.
XML sitemap - this document helps search engines in indexing pages easily by improving their visibility.
Site response time (website speed) - if a site is often unavailable or has a slow server response, this can affect its ranking badly. We suggest solving this problem by choosing the right hosting provider.
Server location - can influence site ranking in different geographic regions. This is very important especially when it comes to geographically-specified searches.
SSL certificate - Google confirmed that it indexes SSL certificates and uses HTTPS as a ranking signal.
Duplicate meta information on the site - these can have a negative influence on the site and even cause its downfall in the results page.
Breadcrumb navigation - or trail tracks, is a building block of good site architecture, helping users and search engines in locating quickly where they currently are on the site.
Mobile optimization - Google recommends creating responsive sites which fit the screens of all mobile devices. Considering an increase in mobile searches, this ranking factor is an important one.
YouTube videos - there is no doubt that YouTube is favored in the results page. You can probably guess why.
Page usefulness - if a site is difficult to navigate in and use, this can affect ranking badly because it will reject users by lowering time, number of viewed pages, and increasing bounce rate.
Using Google Analytics and Webmaster tools - if you connect these tools with your website, you can help Google in indexing and monitoring data on your site.
User comments and site reputation - review sites, such as Yelp, play an important role in the algorithm because they provide Google with first-hand information about your company.
Backlink domain age - backlinks coming from older domains can be more powerful than links coming from new domains. Older websites are trusted more, so it is logical for their recommendation to be valued more as well.
Number of root domains linking to the site - number of different, individual domains linking to a site is one of the most important ranking factors in Google’s algorithm.
Number of pages with incoming links - a total number of pages linking to the site, no matter if the domain is the same, is another important ranking factor.
Alt tags (on images) - alt text on images is the same as anchor text.
Links from .edu and .gov domains - even though Matt Cutts announced that TLD is not a very important factor, many SEO experts still consider that .edu and .gov links still hold a special place in the algorithm.
PR of backlink pages - backlink PageRank is a very important ranking factor.
Link domain authority - an important factor which shows how valuable a link really is. E.g. if a link comes from a site whose page has PR3 and homepage PR4, while another one comes from a page with PR3 and root domain PR8, the latter will have greater authority.
Competition links - if our competitor sites link in the results page, this can help ranking a targeted keyword.
Social shares - a total number of page shares on social networks can greatly influence link value.
Bad neighbor links - links coming from low-quality sites can harm yours.
Guest posts - can improve ranking if content is relevant. Links coming from the post itself are ranked better than author bio links.
Backlinks to a domain homepage where a page is - links to a homepage can be very important in determining link value.
Nofollow links - links with “nofollow” attribute literally tell Google not to follow them. It is uncertain whether they affect ranking, but they sure help in creating a natural link network and can bring referral traffic.
Link type diversity - if a large percentage of links come from one source (forum, blog comment), this can be a spam indicator et vice versa, links coming from different sources can be a signal of a natural linking profile.
Sponsored links - links from pages which contain words ‘sponsored’, ‘affiliate’, ‘partner links’ etc. can reduce link value because they are frequently misused and manipulated with.
Contextual links - links within page content are considered more powerful than those on blank pages or different page positions.
Too many 301 redirect chains - links coming from 301 redirection are of lower value, especially if they are overly used.
Anchor link - anchor text is less important than it used to be in the past, but if too many links with the same anchor text are used, this can signalize web spam.
Internal link anchor text - another ranking factor, but is valued differently than external backlinks.
Link attribute title - a text appearing when cursor is placed on top of a link is another relevance signal, though with a lesser impact.
Links from different TLD domains - if you have links from different TLD extensions (.de, .ru, .es, .co.uk, .rs), this can help you get a better rank in local searches of those countries.
Location of a link within content - the position of a link on a page influences link value. Links situated on top of a content are worth more than links lower in the text.
Backlink domain relevance - the link of a site from a similar niche is more important than links coming from sites which are not in connection with it whatsoever.
Page relevance level - link from a page whose topic is tightly-connected to it is more powerful than a link that is not connected with it.
The text around a link - Google realized that context (the text around a link) is either your site’s recommendation or a negative comment. A link in positive context and with beneficial message is probably weighed harder.
Keyword in title - Google gives extra points to pages which contain your keyword in their page title.
Improvement in a number of links - site which constantly gains links in a time period is rising in the results page.
A drop in a number of links - contrary to the previous factor, a reduction in a number of links can influence ranking and signal a decline in popularity.
Backlinks from Hub pages - getting a backlink from sites which are considered as the best resources on a certain topic (a.k.a. hubs) get a special treatment.
Backlinks from authoritative sites - links from popular and authoritative sites have greater value than those coming from a small, micro site.
Wikipedia links - even though those links are “nofollow”, many experts think that a Wikipedia link means authority and trust in the eyes of a search engine.
Backlink age - Google values older links. They are much more influential than new links.
Links from real sites vs. splogs (spam blogs) - Google will probably give more value to a link coming from real sites than from fake ones (such as splogs). They use brand signals and user interaction to make difference between these sites.
Organic links - sites with organic links will probably be ranked better and resist any change in the algorithm than sites which manipulate link building.
Reciprocal links – in its link schemes document, Google recommends avoiding link exchange.
User-created links - Google is able to make a difference between user-generated links and links from site owners.
Links from 301 redirections - have a slightly lesser value than direct links. Matt Cutts of Google said that redirections have a similar value as direct links.
Schema.org structured data - pages which support structured data are in greater advantage than pages which do not.
DMOZ directory - many believe that Google gives special trust to sites which are listed on DMOZ directory.
Yahoo! Directory - algorithm also gives a special place for Yahoo directory, taking into consideration how much it exists.
Number of outbound backlinks - PageRank is final. A backlink with a great number of external links is valued lower than a link coming from a page with less outbound links.
Links from forum profiles - due to mass spam options, Google reduces the value of links coming from forum profiles.
Number of words from linked content - a link from a text with 1000 words is usually worth more than a link within a 25-word description.
Linked content quality - links from poorly written or spin articles are not as valuable as links with rich content.
Site-wide links - Matt Cutts confirmed that if links are found on all site pages (e.g. in footer), they are compressed and counted as one link.
Keyword’s organic CTR (click-through rate) - pages with many visits and clicks in the results page get more visits from Google.
Bounce rate - it is still not quite clear whether bounce rate is a factor or not, but many SEO experts believe that Google uses visitors as quality testers. Pages which the visitors leave fast are not of great quality.
Direct visits - sites with many direct visits are probably of greater quality than sites with less visits.
Recurring visits - Google also monitors whether people come back to a site or not. Recurring visitors can improve ranking.
Blocked sites - Google disabled this option in Chrome web browser. However, Panda algorithm used this option as quality signal.
Chrome bookmarks - it is known that Google gathers data from Chrome web browser. Pages bookmarked in Chrome can have better advantage in the search results.
Google toolbar data - according to a Search Engine Watch article, Google uses data obtained from a toolbar as a ranking signal. However, besides load speed and malware, it is still unknown what kind of toolbar data they actually use.
Number of comments - pages with a lot of comments can be a signal of social interaction and information quality.
Time spent on the site - Google also pays attention to time the users spend on the site. If they spend more time on it, then the site is of greater quality.
Query deserves freshness - Google supports new pages for some queries.
Query deserves variance - Google has a tendency to show various results for some general searches which might contribute to context and meaning.
User’s search history - in order to get to the sites you frequently visit faster, Google uses your Google user search data and gives them advantage over other results.
Geotargeting - Google gives advantage to sites which are on a server in some state and which have a local country suffix (.de in Germany, .es in Spain, .rs in Serbia).
Safe search - inappropriate language and grownup content do not appear to users who turn safe search on.
Google+ circles - Google gives better positions in results to pages whose authors are in your circles on Google+.
DMCA complaints - Google removes pages which violate DMCA (Digital Millennium Copyright Act) from search results.
Domain variation - this part of Google’s algorithm makes sure that different domains are shown in search results. Their logic is that one domain with different pages is shown in all results on the first page of Google
Transaction searches - Google sometimes shows different results for shopping-related keywords, such as flight reservation.
Local search - Google frequently launches local results coming from Google+ above other results.
Google News - Google favors websites if they appear with keywords in Google News.
Preferring big brands - after Vince algorithm update was rolled out, Google started giving advantage to big brand sites.
Shopping results - Google sometimes shows shopping results in organic search results.
Image results - Google frequently improves search results with images when they are frequently used in image search.
Number of brand results in SERP - domain- or brand-oriented keywords bring numerous results coming from one and the same site.
Number of tweets - just like links, tweeted pages can influence ranking all the same because they too are indexed.
Twitter user’s authority - it is more likely that tweets coming from older, popular users with many followers will have better effect than from users with lower impact.
Number of likes from Facebook - even though Google does not see the names of people who like a page, the number of likes is still visible.
Facebook shares - similarly to backlinks, shares can be more influential than Facebook likes.
Facebook user authority - just like on Twitter, the more popular a page or person who shares the content, the better the effect of that share will be on the ranking.
Pinterest pins - since Pinterest is a very popular social network with many public photos and data, it is very possible that pinned images and content gain on importance.
Social sharing sites’ signals - it is possible that Google uses shares coming from Reddit, Stumbleupon, Digg, etc. as some sort of a signal for better ranking.
Number of pluses on Google+ - even though Matt Cutts said that Google+ does not directly affect ranking, it is hard to believe that Google ignores its own social network.
Google+ user authority - it is logical that Google values +1 by its influential users with a lot of followers than those without one.
Verified Google+ content authorship - verified authorship represents a very influential ranking factor.
On-site social signals - social signals across the site, such as comments, likes, etc. can increase site’s authority and visibility in SERP.
Brand name within the link - branded text within the link is a simple yet strong brand signal.
Branded search - Google will gladly take into consideration how much people search for your brand on Google (e.g. PopArt Studio, PopArt Blog, PopArt SEO ranking factors).
Sites with Facebook page and likes - the official business page with many likes is a good popularity signal.
Sites with Twitter profile and followers - just like on all other social networks, the more followers, the bigger importance.
Official LinkedIn company page - many serious companies have an official page on LinkedIn.
LinkedIn employee check-in – an even greater effect would be achieved if your employees reported that they work for you on LinkedIn (adding current position on their private profile).
Social network profile legitimacy - pages with e.g. 10,000 followers and 3 posts will be treated differently than pages with 10,000 followers and many social interactions.
Brand mentions in Google News - brands mentioned on news sites also gain on importance in ranking.
Mentions - if a site mentions a brand or site, without linking to it, Google still counts this brand mention as a popularity signal.
Number of RSS subscribers - since Google owns the popular Feedburner – RSS service; therefore, it is logical that they monitor the number of RSS subscribers as site’s popularity and quality signal.
Physical location on local Google+ list - real companies have headquarters. It is possible that Google searches location data in order to determine if a site is big brand or not.
Panda penalty - sites with low-quality content, especially link and content farms are less visible in search engines’ eyes after Panda algorithm has hit the Internet.
Links to bad neighbors - links to bad neighbors, such as farmaceutical companies etc., can influence your site’s ranking very badly.
Redirections - sneaky redirections – out of question! Sites that are proved to do this are not only getting a penalty, but deindexed as well.
Pop-ups and distracting ads - the official Google guidelines say that pop-up windows and disturbin ads are a signal of low-quality sites.
Over optimization - includes exaggeration in on-page optimization factors, i.e. using too many keywords all over the site.
Too many ads - Page Layout Algorithm penalizes ad-full and content-free websites.
Hiding affiliate links - using cloak method to hide affiliate links can make your site have bad results.
Affiliate sites - it is no secret that Google does not like partnership programs, so many experts think that it monitors sites who want to monetize their efforts.
Auto-generated content - Google does not approve of auto-generated content. If you site is suspected to have such content, you can expect both penalty and deindexing.
IP with spam flag - if Google flags your server’s IP as spam, all the sites on that server will feel the consequences).
Meta tag spam - Google can punish you if it notices that you stuffed your meta tags with keywords.
Penguin penalty - sites affected by Google Penguin algorithm are less visible in search results.
Profile links with a great percentage of low-quality links - a number of links obtained by black-hat link building methods (blog comments, forum profiles) can signalize that you tried cheating the system.
Relevance of a linking site - Google can suspect you if you have a lot of inorganic backlinks from sites that are not relevant to yours, that is, from sites which are thematically disconnected from yours.
Inorganic link flag - Google sends thousands of warning messages for sites it detects as inorganic. This usually comes before ranking drop, though it is not a rule.
Links from the same IP class - backlinks from sites that are on the same server can show that you manipulated backlinks from your own sites.
Manual penalties - Google can sometimes penalize sites manually. This usually happens if Google team members get an illegal link building warning.
Selling links - this can damage PageRank and visibility of your site in search engines.
Google Sandbox - new sites with an obvious torrent of backlinks are sometimes sandboxed in Google Sandbox, a surveillance regime which temporarily limits your site’s visibility.
Disavow tool - use the disavow tool to remove backlinks with negative impact on your SEO.
Reconsideration request - successful reconsideration requests can clean your site from Google penalty.