what is google rankbrain

What is RankBrain? – Google’s RankBrain Explained

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RankBrain is a machine learning artificial intelligence (AI) that Google uses when it crawls websites and sorts through search results. RankBrain is considered the third-most important ranking factor for Google when selecting the search results it thinks will best match the users. Obviously, this has a big impact on those working away in the world of SEO. Using a complex algorithm that relies on machine learning artificial intelligence, RankBrain is able to figure out the ‘search intent’ of a user. We have delved deeper into RankBrain to shed some light on this search element and what it means for SEO.

What is Search Intent?

Search Intent refers to the user’s ultimate end goal when they’re using a search engine. People look for, process, and use SERPs differently, dependent on what their ultimate goal end goal is, so understanding and optimising for your website to align with a potential customer’s search intent is hugely important for SEO.

For example, someone may use Google to search for a holiday when they’re in the research stage, using the phrase “cheap holidays 2019”. Having these key words and phrases in your onsite content will help you rank for this. When they’ve decided where they’re going, they will be further down the funnel – making sure you have content (in the form of pages, blogs or even gated content) that matches these search queries with relevant, good quality information will increase your chances of meeting search intent.

What Is Google’s RankBrain?

RankBrain is an element of Google’s core algorithm Hummingbird, and uses machine learning (AI) to interpret search terms, decide what they actually mean and bring back the most relevant results. By using an interpretation model, RankBrain is able to apply filters to the search queries. This includes location and keyword phrases, to determine why the searcher has submitted this query.

To allow RankBrain to “teach” itself how to provide relevant results, Google first inputs a range of information from various sources. RankBrain then begins to calculate the data and learns about the different signals. It will then decide which search results best match these signals. Organic search rankings are impacted by the decisions made by RankBrain.

What is Artificial Intelligence (AI)?

Artificial Intelligence (AI) is referred to as intelligence demonstrated by a machine. Technology can be seen to present AI if it can learn on its own. The way RankBrain’s AI works is that it uses search data (past and present) and anticipates future searches. It can also decipher the intent of the search itself.

For example, a Google search for “What is Crawl Budget” gives the user a featured snippet containing the answer. Thus, this fulfils the search intent.

what is crawl budget


However, people search for an answer in different ways. This is where the intelligence of Rankbrain comes into play. It can work out that a user searching for “crawl budget definition” is also looking for the same definitive answer.


crawl budget definition


As RankBrain is an artificial intelligence that is learning over time, it can get information wrong. For example, Google once said that former President of the United States Barack Obama was actually King of America. We all know this wasn’t true. This was later changed after it learnt from its mistake.


king barack obama


When was RankBrain Released?

RankBrain went live in April 2015, but it wasn’t until October that year that the world was made aware. An article by Bloomberg first described RankBrain as an artificial intelligence that converts large amounts of written language into mathematical entries. This allows it to understand the language that has been inputted. When it encounters an unknown word or phrase it can guess based on the data it has already collected.

How Does RankBrain Work? 

RankBrain is most commonly in use when the search query is unique. Through its machine learning it analyses the search term, for example, “England Game” to gain the searchers intent. A relatively vague term like this is where RankBrain becomes indispensable to Google. RankBrain is able to question what type of result you are looking for. For instance, does the searcher want results about England’s next game? Do they want results regarding their games during the World Cup? Or are they attending an England game in London and want directions to Wembley Stadium?

This is a very simple example, but you can see how easy it would be for Google (without RankBrain) to bring searchers irrelevant results. By using a range of databases full of data on people, places and things (otherwise known as entities), RankBrain’s AI can begin to group similar words mathematically into “vectors”. So, when Google gets a query that is vague or unknown it uses these “addresses” and databases to figure out the search intent and produce relevant results.

On the surface, RankBrain is quite simple. Search terms and data is added by Google, these are assigned to certain “vectors” and through machine learning, RankBrain gives you most relevant results to your search entries.

RankBrain & SEO

Reading this will make your wonder “how can I optimise my site for RankBrain?”. Simply put, there is no specific way of optimising for RankBrain. It is largely content driven so ensuring you are producing excellent content is the only way to improve your ranking when it comes to RankBrain. The key is having content that will relate to search terms and hopefully be relevant for uncommon terms too. However, it is really only in the cases of uncommon terms where optimising for RankBrain is useful – which is rare. Therefore, building links to your site and having a good content marketing strategy are still the most important things to consider when trying to improve rankings.

If you’re still unsure, Gary Illyes has a fantastic quote on how to optimise for Rank brain:

“Optimising for RankBrain is actually super easy, and it is something we’ve probably been saying for 15 years now, is – and the recommendation is – to write in natural language. Try to write content that sounds human. If you try to write like a machine then RankBrain will just get confused and probably just pushes you back.

But if you have a content site, try to read out some of your articles or whatever you wrote, and ask people whether it sounds natural. If it sounds conversational, if it sounds like natural language that we would use in your day to day life, then sure, you are optimised for RankBrain. If it doesn’t, then you are ‘un-optimised.”

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