What Are Backlinks?

James Brockbank

Nov 24, 202012 min read
A beginners guide to backlinks

Backlinks — also known as 'inbound links' or ' external links' — refer to links on one website pointing to another website. Building up the number of high-quality backlinks to your site is like getting votes of confidence for your page. Because sites with a high amount of backlinks often rank high in the SERPs, link building is a crucial part of your SEO efforts. 

Backlinks are one of the most important SEO ranking factors. In fact, earning authoritative links is considered to be one of the most important ranking signals used to rank websites.

Additionally, getting a backlink from a reputable source is a great way to raise brand awareness and recognition. 

But what makes a high-quality backlink? 

Trust is a huge factor — if a site with a great reputation links to your site, that's an amazing vote of confidence. If you only have sites that Google finds spammy linking to your website, it's not likely to do you any favors.

Popularity is another factor. Because Google views backlinks as votes of popularity for a website or webpage, there is a strong correlation between sites with lots of (quality) backlinks and better rankings.

See this link on Wired’s review to the GoPro Hero 8 Black?

example of a backlink in a news article from a trusted source

That is one of GoPro’s backlinks. It points from an article on Wired to a product page on the GoPro website. 

And these ‘shop now’ links to Microsoft, Walmart, and more on Oculus’ ‘where to buy’ page? They're backlinks too.


Any link from someone else’s website to yours is a backlink, but you will soon learn that not all links are created equal. Just as you would trust a recommendation from someone who you respect over someone you have never met before, Google trusts backlinks from trusted, authoritative websites over those from those which are either less trustworthy or unknown.

This trust comes in the form of PageRank, one of Google’s algorithms that evaluates the quality and quantity of backlinks pointing to a page to determine a relative score of that page’s importance and authority.

As mentioned, not all backlinks are the same. Let's learn about the different types of backlinks your site can acquire:

We have already shared that links are like votes for trusted resources, but what if you don’t want to vouch for a website but still need to link to it? Nofollow links use the rel=”nofollow” attribute to inform Google and other search engines that they shouldn’t pass trust (PageRank). A nofollow backlink looks like this:

<a href="https://www.domain.com/" rel="nofollow">this is a nofollow link</a>

Given that nofollow links don’t pass PageRank, they won’t necessarily help you rank higher on the SERPs. However, Google announced in September 2019 that they were evolving the nofollow attribute. When nofollow was introduced, Google would not count any link marked this way as a signal to use within our search algorithms. This has now changed. All the link attributes are treated as hints about which links to consider or exclude within Search.

There are some who believe that this change to being treated as a hint means that Google will pass trust through nofollow links in some instances, such as when an authority news platform adds the attribute sitewide. 

Quite simply, a followed link is one that does pass trust (PageRank), and, therefore, does not have the nofollow attribute added. 

Note: there is no ‘follow’ attribute as any link is considered dofollow unless an attribute is added. 

A dofollow backlink looks like this:

<a href="https://www.domain.com/">this is a follow link</a>

Sometimes, you might pay a blogger or influencer to promote a piece of your content or to post a review of one of your products. If money, or a product or service, has changed hands in return for a link, a rel=”sponsored’ attribute should be added to inform Google. 

As a word of warning, paying money or gifting to get a followed link back to your website from another is a violation of Google’s Webmaster Guidelines and can negatively impact a site's ranking in search results. 

The rel=”sponsored’ attribute stops your site from being negatively impacted by these links. 

A sponsored backlink looks like so:

<a href="https://www.example.com/" rel="sponsored">this is a sponsored link</a>

Another of the new attributes rolled out in 2019, UGC (user-generated content) links are those that come from the likes of forums and blog comments. The attribute informs Google that the link has been placed by a user and not the webmaster.

A UGC backlink looks like this:

<a href="https://www.example.com/" rel="ugc">this is a UGC link</a>

Now that we've discussed the types of backlinks, let's find out how to determine the quality of a backlink. Using the Backlink Audit tool, you can view how many backlinks your site has, the referring domains of those backlinks, the toxicity of those sites, and more.

The overview page gives you a summary of the most important information.


You can dive deeper into the reports in this tool to view your top referring domains as well as view metrics related to your backlinks, like Authority Score and Toxicity Score.


You can also integrate Google Search Console and Majestic to ensure you don't miss any backlinks pointing to your site.

The goal is to get backlinks from high-authority sites that are relevant to your website. Here are some factors that determine if a backlink is quality:

  • High number of referring domains
  • Placement on the page (the higher up on the page, the better!)
  • Contextual backlinks (links surrounded by related content on the page)
  • Relevant anchor text

Of course, as mentioned previously, the way Google assesses authority is through their PageRank algorithm, but that’s no longer a public-facing metric since they stopped updating, and subsequently retired, their PageRank Toolbar in 2016.

You can learn more about PageRank and how this applies to link building in 2021, however when assessing whether a link is high quality or not, consider factors such as credibility and whether the site shares quality content of real value to users.

Earn Backlinks from Quality Sites

with SEMrush Link Building

ADS illustration

The wrong links can harm your website’s ability to rank, or even negatively impact any rankings you already have. ‘Bad’ links are often referred to as toxic or unnatural links.

Toxic backlinks are those that typically come from low-quality or suspicious websites or that are in direct violation of Google’s Webmaster Guidelines and exist solely to try and manipulate search engine rankings. This could mean paid links that aren’t marked with nofollow or sponsored attributes, those from low-quality directories or bookmark sites, widely used footer links, or an unnatural number of links that use exact match anchor text.

You can also use the Backlink Audit tool to review your backlinks and identify potential toxic or unnatural links. 

Backlink audit tool screenshot of results

Once the analysis is complete, you can choose from a number of actions including generating a disavow list and submitting it to the Google Disavow Tool. Leave links in your 'remove' list if you want to contact a site manually to request removal, or simply whitelist any links you know are safe.

Backlink audit tool data received

If you need to clean up toxic links and request removal, you can do this directly through the Backlink Audit tool.

Google rewards and passes the greatest authority through those that are editorially placed or vouched for by the site’s owner. An editorially placed or earned link is one where a journalist or webmaster has taken the decision to link to another website or webpage due to it being deserved of being sent traffic and authority. The reason for the link is to enhance a reader’s experience, not to manipulate search engine algorithms.

You see backlinks talked about a lot, and there is no denying that they are an important area to focus your efforts on improving. But why?

They Will Help You Rank Higher

Without great backlinks pointing to your site, you miss out on one of the most important ranking factors, one which helps to showcase that you are a trusted authority in your industry and, therefore, deserve to rank at the top for key search terms.

In fact, having a higher number of backlinks correlates with higher rankings on Google.

They Are One Way That Google Finds New Pages 

Google’s spiders (Googlebot) uses links to find new pages on the web — this is one of the main ways how content is discovered, crawled, and indexed. One way to think of links is as the way in which Google navigates the web. A link from a trusted source will help your content to be indexed by Google faster, meaning it can possibly rank more quickly.

They Boost Your Trustworthiness & Credibility

Great links from authoritative and trusted sources help you to rank higher from an SEO perspective, but they can also help boost your trustworthiness and credibility as a business. Think about it this way — let’s say you are a tech startup. There is a good chance not too many people know about your business (yet).

So, if you manage to land some press coverage and a link from TechCrunch, you will get a serious credibility boost from that. If you then go on to gain links from the BBC, TechRadar, and Wired, that is some serious industry authority talking about you and sending traffic to your website.

Even if we ignore the SEO value, having journalists and editors at key publications in your industry who choose to link to you goes a long way to show people are talking about your business, and that is worth its weight in gold.

They Send Referral Traffic to Your Page

When the web first launched, links were solely navigational. The purpose of links, in the most simplistic form, is to take web browsers from Page A to Page B, not just within one website but also between different sites. And while links are now used as a ranking factor by Google, the principle hasn’t changed that great links send very valuable traffic to your page.

If we step back to the example above, relevant press coverage can (and will) send interested readers to your site. This, in turn, introduces your brand to new audiences who could turn into customers. You have also then got the ability to add this traffic to a remarketing list to target across paid media channels to make your referral traffic work that little bit harder. 

Checking sites for backlinks is helpful whether you're planning a link building campaign or benchmarking your site against competitors' sites. You can get insights about your backlink profile from tools like Google Search Console, but you'll get more detailed information when using Semrush.

Google Search Console will give you an insight into what your own link profile looks like, but it won’t give any information about your competitors.

To start, head over to Google Search Console and log in. Using the left-hand menu, navigate to Legacy tools and reports > Links

You should then see an overview of your website’s backlink profile under the ‘External links’ heading.

Google search console screenshot with backlink data

You will be able to see insights into:

  • External links - How many external links point to your site.

  • Top linked pages - The pages on your site that have the most backlinks pointing to them.

  • Top linking sites - The website which links to yours the most times.

  • Top linking text - The most common link anchor text used for external links.

You can also export your site’s external links as a CSV file in the top right corner.

Start by using our Backlink Analytics tool to gain insights into a whole host of metrics and data points to help you to develop a better strategy. Once you have loaded up a domain into the tool, you are ready to start gaining a deeper insight into the site’s link profile.

Unlike GSC, Semrush allows you to get insights on your competitors' backlink profiles as well. You'll also get more detailed data to analyze (and can integrate GSC with the tool as well!).

The main metrics this tool provides are: 

  • Authority Score
  • Referring domains
  • Backlinks
  • Monthly visits
  • Keywords
  • Overall toxicity score

You can click each number for a more detailed corresponding report.


The Overview tab will show highlights from up to five websites at a time. Click through any widget to access the more detailed report.


You can also export data to a PDF, whether you need to further analyze yourself or send competitor research to a client.


Using Backlink Analytics, you're able to find the following information about a site's backlinks:

  • Overall number of backlinks
  • Pages with the most backlinks
  • TLD (top-level domain) distribution
  • The categories of their referring domains
  • Referring domains by Authority Score
  • Top anchor text for backlinks
  • Link attributes (i.e. follow, nofollow, sponsored, or UGC)
  • Similar profiles (domains with similar link profiles that could be useful for link building opportunities)

Whether you'd like to analyze your own backlinks or see how your competitors are doing, this tool is a great place to start.

How do you actually go about building backlinks? You can read out guide to link building for a full overview, but here are a few key link building strategies:

1. Ask your suppliers to link to you

2. Use HARO (Help a Reporter Out) to respond to requests from journalists

3. Write a guest blog post for an industry publication

4. Use niche-specific directories

5. Turn brand mentions into links (which is easy to do with the Brand Monitoring tool

6. Create ebooks, guides, etc. in hopes of being cited as a resource

7. Publish research and pitch it to the press

8. Analyze your competitor’s backlink profile to identify opportunities

Whether you're looking to analyze your own backlink opportunities or want to see how your competitors are doing, you can use the Backlink Gap tool.

Simply enter your domain alongside your main competitors to get started:

Semrush backlink gap tool

It is a great way for you to identify gaps in your competitors’ link building strategies and prioritize opportunities where you have established that one or more competitors have earned links from a domain that you haven’t.

Backlink gap tool data example from SEMrush

Link building has changed significantly over the last decade, but it is for the best. Here are some common myths to take note of before beginning your link building strategy:

  • The more links you have, the higher you will rank — Not all links are equal, so many links from a spammy site wouldn't carry the same weight as a link from a top industry publication.
  • You shouldn't bother earning nofollow links — Historically, nofollow links haven't had an impact on SEO performance. However, many SEOs believe that Google may choose to follow nofollow links at times (for example, when top-tier newspapers automatically apply the nofollow attribute to all of their sites). Even so, links that are relevant and from trusted sources are still helpful!
  • Buying Links is a Quick Way to Boost Your Rankings — Buying links (or gifting free products in exchange for links) is a direct violation of Google's webmaster guidelines, so you'll want to avoid this so you don't get a penalty. If you are sponsoring content for other reasons besides getting a link, you need to be using the rel=”sponsored” attribute. 
  • You Receive a Penalty if You Earn Too Many Links — As always, quality over quantity! Avoid shady link-buying practices and you'll be good to go.


Backlinks are a key ranking factor and one which you can’t ignore if you want to rank higher on Google. Link building is an expansive field of SEO in its own right, and you will find many specialists who focus only on this area, but the good news is that there are plenty of ways you can get started with quick-win tactics such as those we have listed above.

Build great links, and you will see an increase in your rankings; just be sure to keep an eye out for what your competitors are doing and jump onto fresh opportunities as quickly as you can.

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331Referring Domains
Author Photo
James BrockbankJames is Managing Director of award-winning digital PR and SEO agency, Digitaloft, and has been involved in search marketing since the mid-2000s. He‘s a regular writer on topics including link building, content marketing and ecommerce, having previously contributed to the likes of Search Engine Journal.
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