SEO fundamentals: Google’s search algorithms explained

For every online search, there are potentially millions of websites that contain what the searcher is looking for. To decipher which results provide the most value, Google Search uses algorithms that are based on certain factors. Find out what they are, and how you can keep ahead.


7 min read

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Cobiro's Content Team

This is the fourth in our series looking at the principles of SEO. Check out our other posts on setting up your website for SEO, writing compelling content and creating a link building strategy.

What is an algorithm?

An algorithm is a logic-based, step-by-step action for solving a particular problem. In Google’s case, it’s the process of providing search results that make sense to the searcher. Google’s ranking systems shift through billions of webpages in its index to find the most relevant and useful - which takes place in a split second. These ranking systems are made up of a whole series of algorithms, rather than just one. 

The five ranking factors

To provide the most relevant information, Google’s algorithms look at five factors when performing a search. The weighting it gives to each depends on the nature of the query. If someone is searching for the latest movie news, it will place a greater emphasis on ‘fresh’ content, i.e. content that’s new or recently updated. If someone is searching for advice on second hard cars, it may prioritize websites that are recognized as reliable and trustworthy.

1. Meaning of the query

To return relevant results, Google’s language models are built to figure out what strings of words it should look up in its index. They assess what the words mean in everyday language, the intent (if a searcher is looking for a definition, review or specific thing) and the need for timely content - for example, the latest MLB scores. 

2. Relevance of web pages

Google’s algorithms look at the content of web pages to determine if the page contains the information the searcher is looking for. This is where keywords come into play. If your web  page features the same words as what’s in the search query, the information is more likely to be relevant, and therefore have a higher chance of being ranked. 

3. Quality of content

Search algorithms also place a big importance on providing reliable sources by reviewing the expertise, authoritativeness, and trustworthiness of a topic. It does this by looking for sites that other users appear to value for similar queries. This evidence is gathered in the form of backlinks. Backlinks are where other websites contain links to your website, and Google’s algorithm analyses the quantity and quality of these when searching for pages.

Learn how to create an effective link building strategy.

4. Usability of web pages

How easy and accessible web pages are to use is a key focus when determining which websites to rank. Google’s algorithms look for indications that a website will format correctly across all browsers, if it will work on all types of devices, how quick the page load time is and how secure it is.

5. Context and settings

Search results are impacted by the individual circumstances and preferences of the searcher. Google uses information such as location, search history and settings to help tailor its search results at that given moment. So if you search for ‘best restaurants’, those that are within close proximity to you are likely to appear in the search results.

Use our free SEO app to optimize your ranking.

Google updates its algorithms all the time

As search behavior evolves, so too does the technology that underpins it. If we take the rise of mobile search as an example, this has led to people looking for information close to where they live, impacting on the type of information they expect to receive. Other issues such as spamming, low quality content and unreliable backlinks mean that algorithms are updated on a continual basis.

Many of the updates happen seamlessly in the background, but there are major ones that happen from time to time, which can have a lasting impact on SEO strategy. Here’s Google’s archive of all the search updates that have taken place since 2005.

Explore Google's latest page experience update.

How to stay ahead

It can be hard to predict what the future changes will be, but it’s worth remembering that search engines are designed to serve people. Google’s goal is to provide the best user experience possible, so with that in mind, we’ve put together a few suggestions on how to keep your website competitive.

Think about the nature of your business

It’s worth reflecting on what your business is trying to achieve, from an online perspective. If it’s providing the latest news and industry information, make sure there’s a healthy supply of fresh content that’s continually kept updated. If you’re positioning it as a thought leader, focus on your linking strategy to build authority. That’s not to say that other areas of your SEO strategy should be neglected, but it’s never a bad idea to focus on your strengths.

Explore our five point guide for improving your SEO performance.

Adopt a mobile-first mindset

In 2020, mobile devices took a 51.6% share of web traffic, up from 35.1% in 2015. Mobile is here to stay, so it’s vital that your website is set up to perform for this, which in turn, will help Google’s algorithm find and rank it. To improve its chances, keep things simple. A clean, well maintained site that’s easy to navigate is more likely to do well. It’s also important to keep your content clear and accessible, tailored towards smaller devices.

Get useful tips for creating impactful, SEO-optimized content.

Build a fast website

Having a fast website is intricately linked with Google’s drive for creating the best user experience possible, and it means that it can crawl (check for updates) it more easily, helping its indexation. It also makes business sense. We know that for every second delay in mobile page load, conversions can fall by up to 20%, so focusing on your site speed can bring huge benefits.

Create a lightning-fast JAMstack website for free. No coding or installation required.

Consider using Google Ads

We’re veering off topic here (search listings are always free - no one can pay for a better ranking), but if your business has an advertising budget, it's worth thinking about investing in Google Ads. These allow you to bid on keywords (via an auction process) to display ads at the top of search results, which are then shown to users who have searched for these keywords. 

Learn more about Google Ads and how Cobiro’s bid engine can help you win the bidding auction.


Hopefully you’re more up to speed now with how Google’s search algorithms work. If you’re ever in doubt, just remember to put the user at the heart of everything you do. If you can understand what their needs are, and shape your efforts around those, the chances are you’ll soon start to see the better results.

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