If you have been actively trying to drive organic traffic to your website for some time now, and possibly dived deep into the world of link building – the chances are that you have at some point wondered this: What makes a link valuable? 

We have the answer for you. We have shortlisted some factors that can possibly affect the value of backlinks. Nothing works in isolation when it comes to SEO, so these factors interact with each other as well. Of course, there are variables and exceptions, but with an understanding of these factors, you will be in a better position to get the ‘results’ you want.

Search engines assign a higher level of trust to your website if prominent websites link to it. It’s like a way to measure relevance. There is such a thing as a bad link. You would do well steering clear of links that don’t benefit you in the long run, no matter how tempting. 

  • So what makes a good link? 
  • What efforts can you make to increase the value of backlinks? 
  • What are the factors that affect the value of links? 
  • We are sharing most of the useful information in a nutshell. 

Some of the boxes below feature extracts from relevant Google patents that seem to provide some support for our suggestions. Although much of the information is based on theories that evolved around Google patents, there is some evidence that other search engines may also be following a similar model.

Factors Affecting The Value of a Backlink

Here is a rundown of all the factors which can affect the value of a backlink.

  1. Placement in the main content:

The star of a show must be seen on the main stage, rather than in the wings or backstage.

For a link to be of higher value, it should be in the main text area (the stage) of the page. This placement is preferable as compared to placement in the sidebars, headers, or footers (also known as boilerplate).

Patent: Classifying sites as low-quality sites patent: https://patents.google.com/patent/US9002832B1/en
“The system optionally discards candidate resources linking to the site only from a boilerplate section..… the system can discard a web page linking to the site only from a navigation bar of the web page. The system discards candidate resources by not receiving resource quality scores for those candidate resources or by not using resource quality scores for those resources in determining the link quality score.”

The value of backlinks is high if they are considered as being editorially placed. The link placement should seem natural, logical, relevant, and preferably of the site owner’s own accord. 

Links that are a part of advertising, directories, user-generated content, cross-site widgets, and similar other sections are not considered editorially placed, so it follows they won’t have as much value. 

  1. A prominent higher position in the main content: 

Drawing on our earlier analogy, the star of the show needs to be in the limelight. 

If a surfer came upon a page and saw two links, one higher up in the main content and at a prominent position, and another one in an insignificant bottom corner in the last few paragraphs, which link is the surfer likely to click on?  

Search engines will also give more weight to a link that is placed in a higher and more prominent position because such a position increases the probability of the link being clicked by people. 

Patent: Method for node ranking in a linked database
“Links can also be weighted by their relative importance within a document. For example, highly visible links that are near the top of a document can be given more weight.”
  1. Link from a popular page:

In the business world, what would happen if the services of a quality startup were recommended by the leader of a large multinational? 

Instant credibility! 

It works on similar lines in the world of links as you’d expect. The link from a popular page (i.e. a page which has a lot of its own links and/or has a lot of organic traffic) passes on more value.  This concept formed some basis for the old “Page Rank” metric which Google used to use. 

Now don’t forget that all factors interact with each other, and you have to consider also the “value” of the links that page has – but assuming that is satisfied – the more links the page has, the more link equity it can then pass on. 

Patent: Method for node ranking in a linked database

“…a citation from a highly ranked backlink as more important than a citation from a lowly ranked backlink (provided both citations come from backlink documents that have an equal number of forward links).”
  1. Relevance of the anchor text:

Visitors are more likely to click on links that they think will serve their purpose. How do they gauge whether the link is going to be of use to them? It is through the anchor text. 

If you want to bring in more interested traffic to your website, the links to your site must have contextually relevant anchor texts.

This is both for click-through reasons, but also the anchor text will be used by search engines as a gauge for understanding what that link is about, and subsequently, what keyword rankings it’ll impact. 

Google’s patent below shows that its not even just the anchor text which impacts this, but also the text surrounding it. 

 You also don’t want to over-optimize anchors however, so just ensure to use a natural mix and in line with what is favored by the SERPs (We’ll discuss this in more detail in another article). 

Patent: Method for node ranking in a linked database
“Thus, even though the text of the document itself may not match the search terms, if the document is cited by documents whose titles or backlink anchor text match the Search terms, the document will be considered a match….
In addition to or instead of the anchor text, the text in the immediate vicinity of the backlink anchor text can also be compared to the search terms in order to improve the search.”
  1. Links from unique websites: 

The value of backlinks increases when they are from websites that have no previous links to you. It is like a measure of popularity. 

Your website receiving backlinks from different websites is akin to receiving their votes. Multiple votes coming from the same source, or one vote each coming from different sources, which do you think will matter more?

Backlinks from different websites tell search engines that your website is popular, rather than simply being favored by a few sources. 

But from a marketing point of view, you should also consider that more than 1 link from the same website can have other benefits. Brand awareness and driving referral traffic, for instance. 

If you had the ability to get multiple links from a popular site like TechCrunch or Forbes though, I would always say it is a good thing. 

Patent: Classifying sites as low-quality sites patent
“….To determine the link quality Score, the link engine can perform diversity filtering on the resources. Diversity filtering is a process for discarding resources that provide essentially redundant information to the link quality engine. 
…Because both resource A1 and resource A2 belong to the same site, site A, the link quality engine can discard one of those resources and select a representative resource quality score for both of them.”
Additionally on the same patent (seems like it is to filter out link schemes/networks)

“…the system can determine that a group of candidate resources all belong to a same different site, e.g., by determining that the group of candidate resources are associated with the same domain name or the same Internet Protocol (IP) address, or that each of the candidate resources in the group links to a minimum number of the same sites.”
  1. External backlinks:

You could consider this an extension of point 6. The value of backlinks from other websites will be more than the links from one page to another of your website. 

To understand this better, consider the example of a product of your company. What people outside the company say about your product is more valuable than what the employees say about it. The opinion of the employees does hold value, but the approval of the outsiders matters more. The pages of your website are like your employees. 

Search engines will also give more value to what other websites have to say about your website. Collating points 6 and 7 together, we can say that you should try to get more backlinks from external unique websites to get more traffic and boost your search rankings. 

  1. Backlinks from relevant websites:

In any business, the opinion or vote of someone with knowledge in the same field holds more value. The concept is similar. The value of backlinks from websites relevant to your website’s content would be relatively higher than the ones from random websites.

Now where it gets tricky is the concept of “relevance”. 

If a site sits perfectly within your sector and the target audience is also your target audience – that’s obviously the perfect fit. 

However, it does not mean that if a site is only in a tangential industry/crossover sector, that the link will be less powerful. For example, let’s say you have a site in the real estate industry, and you get a link from the wedding industry.

There are different degrees of relevance, and as long as the site is linking in a contextual way, and it has logical relevance, I would argue it’s a link worth going for. 

Patent: Method for node ranking in a linked database
“Rather than determining relevance only from the intrinsic content of a document, or from the anchor text of backlinks to the document, a method consistent with the invention determines importance from the extrinsic relationships between documents…
Not all citations, however, are necessarily of equal significance. A citation from an important document is more important than a citation from a relatively unimportant document. Thus, the importance of a page, and hence the rank assigned to it, should depend not just on the number of citations it has, but on the importance of the citing documents as well.
…rank of a document is a function of the ranks of the documents which cite it.”

Another patent can be added to further substantiate the impact of relevance. If we look at “Scalable system for determining short paths within web link network” patent, it talks about the concept of ‘seed sites’ and that they are broken down by topic. Seed sites are essentially what Google considers as trusted sites. 

So this suggests the seed sites are broken down into shards – shards represent topics and niches. At TLG, we believe this goes beyond the simplistic explanation of top-tier sites like New York Times and Wikipedia being trusted sites – and that its actually about how relevant that site is, to that topic or niche. I.e. its ‘topical authority.’

The original TrustRank algo was biased toward big sites, but they later created a new form of Trust Rank called Topical Trust Rank. The aim of Topical Trust rank was to separate the web into  those shards.

Patent: Scalable system for determining short paths within web link network
“The system divides a link graph of nodes into shards (310) and assigns each of the shards to a server (320). The system calculates, in parallel, a nearest seeds distance table for each of the nodes in each shard (330). Using the final result of the calculation, the system ranks the nodes (340). For example, web pages associated with shorter nearest seed distances may receive higher page rankings. Generally, as distance other than the distance to the closest seed is used. In some implementations, the third closest seed is used in calculating a ranking.”
  1. Freshness:

The value of backlinks from fresh pages (new or updated)  might be higher than those from stale pages. 

Stale, in this case, is not synonymous with old. A page is stale if it has outdated content, it is not updated, the user engagement is declining, and it does not get many new links over time. 

An old page, on the other hand (one that is updated/ keeps getting relevant new links), can be a powerhouse of value. It is like being recommended by an expert with years of experience. Even an old backlink on such a page may hold more value. 

Patent: Method for node ranking in a linked database
“it is appropriate to assign higher value to links coming from pages that have been modified recently since such information is less likely to be obsolete.”
  1. The link growth rate:

If the number of new links to a page is growing, it may signify to search engines that a page is fresh and/or relevant. This will likely boost the page ranking. 

On the other hand, if a page is getting sporadic backlinks as time goes on, it may signify that it is growing stale and losing its relevance. It is more likely to be devalued.

This is essentially what some in the industry call “link velocity”. Definitely an important factor when you look at it from a domain-level perspective, but also when it comes to individual pages. 

As long as you are building links through non-spammy methods (i.e. not using “black hat methods), there also isn’t any need to worry about being penalized through link velocity that’s too high, that is generally a myth. 

Patent: Document scoring based on link-based criteria: https://patents.google.com/patent/US8407231B2/en
“It may use the inception date of a document to determine the rate at which links to the document are created (e.g., as an average per unit time based on the number of links created since the inception date or some window in that period). This rate can then be used to score the document, for example, giving more weight to documents to which links are generated more often.”
  1. Spam and low-quality links:

Links that do not meet quality standards will most likely be ignored by search engines eventually. You would do well to stay away from spammy and manipulative links. 

It could be argued even some low quality links do have (some) effect, and we have seen some cases where most of the competition has been propped up on a profile of low quality. 

However, even though your site may not be penalized directly, rankings may go down later down the line – because those links are then determined to no longer be valuable, and you lose that link equity. 

As the below diagram from the patent shows, there are multiple factors which will determine whether a link is “low quality” or not. For a search engine like Google, this is ever-changing, therefore, it’s better to build links the right way from the start. 

Patent: https://patents.google.com/patent/US9002832B1/en

Fig 3.

  1. Outbound links to authoritative sites:

Linking to authoritative content is a practice based on a 1998 algorithm research paper and on a seminal document by Brett Tabke, who is known as one of the fathers of modern SEO. More info here.

It might have a positive impact on your search engine rankings if your page bears links to high-quality authoritative resources. However, above all else, it is paramount to have good content with logical links to high-authority sites. Pages that link to authoritative content (may) have a higher value than the ones that do not. 

This is not based on anything that Google representatives have said, and nor do their patents describe this as a ranking factor. John Mueller also attempted to discuss this area in this video but fell short of confirming if outbound links could help your SEO in some way. 

He did say however, 

“In the most common cases however if you’re linking out naturally from your content to other sites that offer additional value and more context then that’s fine and there’s nothing special that you need to do.” 

So outbound links could at least help users, it improves the experience that user has on that page – which could indirectly improve your SEO and lead to more links. 

  1. Placement within a page with outbound link(s) to spam:

The value of backlinks will most likely suffer if they are placed on pages with outbound links to spam. You know the proverb ‘One rotten apple spoils the barrel’. This is a similar concept. The spam link will drag down the value of your link. 

The search engine ranking may also suffer if there is a hint or a whiff of unnatural paid links, or of the website being a part of a manipulative blog network or link scheme. 

  1. Nofollow links may offer some value:

The nofollow attribute indicates to search engines that they must ignore that link and that the website does not endorse it (that it does not count as an editorial vote). 

People assume that nofollow links make zero difference to ranking. However, nofollow links may have some value, more so if they have come from especially high quality, relevant sites. They may act as some sort of signal. These links can also still build brand awareness, build trust, create a more natural looking link profile, and the increased visibility could even indirectly lead to dofollow links as well. 

We especially do see this a lot in PR link building, where many media sites have a policy of nofollow links. 

Ranking search results patent: https://patents.google.com/patent/US8682892B1/en
“…An implied link is a reference to a target resource, e.g., a citation to the target resource, which is included in a source resource but is not an express link to the target resource. Thus, a resource in the group can be the target of an implied link without a user being able to navigate to the resource by following the implied link.”
  1. Link to the same URL more than once:

This is for cases where you have more than one link coming from the same source. As we said before, you generally want to build links from unique domains. But let’s dive a bit deeper into what happens with these “non unique” links. 

There are two scenarios:

  • Internal links: This is when two links to a page on your website appear on another page on your site. In this case, the first link has more priority and only the first anchor text will count for ranking. So if you want the link to rank for some specific anchor text, use that anchor text for the first link.
  • External links: When a page on another website links to a page on your website multiple times, only the first link has value, and the consecutive links are ignored. 
  1. Robots.txt and indexing blocks:

Search engines can rank pages only when they index them. To index, they follow and crawl the pages. 

A robots.txt file informs the crawlers about the pages they are allowed or disallowed to crawl. Search engines may still index the pages (the ones they are not allowed to crawl due to robots.txt) if other pages link to those with descriptive texts (helps the search engines gauge the content without actually going through it). 

Robots meta tags or X-robots tags set to noindex and nofollow will prevent search engines from crawling and indexing that page. Any outbound links on that page won’t be followed, and won’t pass any value.

  1. Link stuffing

Stuffing links in a page is bad for a variety of reasons. Link stuffing leads to poor user experience. Users will likely get overwhelmed seeing a large number of links strewn across the page. They may leave the page without clicking on any. 

In addition, there is to some extent some “dilution” of link equity when a page has multiple outbound links. 

Search engines want to optimize searches and present relevant results. They look very unfavorably upon pages loaded heavily with links. 

The exception to this may be if you do resource page link building. In those cases, let’s assume it is a decent quality site, only linking to pages which have some logical relevance – that itself should act as a signal which outweighs the impact of having those other outbound links. 

  1. Anchor text diversity:

The anchor text of your backlinks shouldn’t be an exact match for your target keywords. If you try over-optimization of your anchor text because you want your page to rank for the specific text, it may become problematic. 

If search engines suspect unnatural link building, (which they will if all of your backlinks have the same pattern of anchor texts), it might negatively affect your ranking. 

So you really want a rich diversity of anchor texts. You should go for a healthy mix of anchor texts including your keywords, branded ones, and unique words. 

Patent: Ranking based on reference contexts:  https://patents.google.com/patent/US8577893B1/en

“…may use the number of different contexts (which may correspond to the number of entries in the list) for a document to determine a ranking score for the document. Other factors in the set may include the number of links to the document, the importance of the documents linking to the document, the freshness of the documents linking to the document, and/or other known ranking factor. 
The patent makes references to “context identifiers”. The way it seems it is being used is that it looks for these “context identifiers” and where there are not a lot of the same identifiers, or where there is a sudden surge of them – may be considered suspicious and won’t be counted as a ranking factor. “
  1. Backlink clicks:

The volume of backlinks to your website must have a reasonable relationship with the traffic it receives. Search engines can analyze relevant, reliable websites in your niche and create a traffic benchmark. If there is a discrepancy between the traffic and links (huge number of backlinks, hardly any traffic), it could raise suspicion. 

Also when it comes to guest posts, limit your backlinks in those posts, and refrain from stuffing it with links. Additionally, do not allow your backlinks on fake, spammy websites, because they generally won’t have much traffic (or relevant traffic.)

This is where it’s important to partner with a link building agency that can not only build links on good quality sites, but will also handle any guest posting opportunities with care.

Patent: Determining a quality measure for a resource: https://patents.google.com/patent/US9558233B1/en
“ a seed resource that has a disproportionately large resource link count relative to its selection count may be assigned a low seed score as the links do not generate a proportional amount of traffic to the seed resource.”
  1. Proximity to trusted seed set: 

We touched on this in number 7. How close a site is to a trusted seed set affects the boost it gets. The value of backlinks from a site that is close to a trusted site is more than those from sites further away.

While a lower quality site, will naturally be further away from that trusted seed set, and will have less value. 

Yahoo were the first to develop something akin to a “TrustRank” patent. Google also has their own version of TrustRank, which we’ve taken from an extract in the second patent shared in the box below.  

On top of this, links from sites with a good reputation and accurate information also have a higher weightage/trust with search engines. This is especially important when it comes to Your Money or Your Life (YMYL) Topics, which is particularly important if you’re in the health, or finance industry. The way YMYL is assessed is outlined in section 2.3 of the Search Quality Raters guidelines.

As explained in point 7 though, the revised version of TrustRank was designed to ensure there was not a bias towards big sites.

Patent: Producing a ranking for pages using distances in a web-link graph: https://patents.google.com/patent/US9165040B1/en
“In one embodiment of the present invention, seeds 102 are specially selected high-quality pages which provide good web connectivity to other non-seed pages.”
Patent: Search result ranking based on trust: https://patents.google.com/patent/US8818995B1/en
“A search engine system provides search results that are ranked according to a measure of the trust associated with entities that have provided labels for the documents in the search results. A search engine receives a query and selects documents relevant to the query.The search engine also determines labels associated with selected documents and the trust ranks of the entities that provided the labels. The trust ranks are used to determine trust factors for the respective documents. The trust factors are used to adjust the information retrieval scores of the documents. The search results are then ranked based on the adjusted information retrieval scores.”

While these are some of the factors that may affect the value of a link, it is extremely difficult to gauge the effect of one in isolation from others or do any kind of exact calculation of the weightage of one against the other. 

However, using links to build trust is a long-term process that involves quite a lot of variables. 

How TLG Can Help You?

If you are looking to hire a link building services agency, its important to ensure that the agency has a strong understanding of the fundamentals of links, and what makes them valuable and high quality – and not just an arbitrary, half-baked understanding. 

Concepts like link velocity, domain-level and page-level relevance for instance, go beyond the basics. It’s not something that every SEO agency or link builder is aware of – but for us, that’s our bread and butter. 

That’s where we can help. We go beyond just building links for the sake of links – we put a process in place where the backlink value is at the core of what we do.

And by doing this, TLG can help you navigate the world of links with best practices so that you climb the rankings, while avoiding the risk of penalty and low-quality link building.