Link Building Metrics

There are various metrics associated with links that you should be aware of. These metrics can help you judge the value of a potential link, helping you assess whether it’s worth pursuing and how many resources you should put into acquiring it. Knowing these kinds of metrics is also useful when you’re doing link profile analysis (a holistic report of the number and types of links on a website), whether on a competitor's website or your own.

It’s also important to understand how different link attributes can affect how valuable the link is when it comes to organic search rankings. Measuring the impact of link building can be tricky, but understanding these elements will help you with this process.

One of the easiest ways to understand how strong a domain is, especially relative to other domains, is to use Domain Authority.

Domain Authority is calculated by Moz and runs on a scale of 0-100, with 100 being the highest. It uses a number of signals taken from the Moz crawler and tries to predict how well a domain will perform in search results. It is useful when trying to get a rough idea of how strong a particular domain may be.

There will be occasions when you have the opportunity to get a link from a page that already exists on a website, as opposed to a new page that is created for a blog post or news item. An example could be an existing list of some kind to which your link gets added — perhaps your coffee shop is added to a page with a list of the best espresso in Seattle.

In cases like this, you should assess the strength of the page so that you know how worthwhile the link is to you before you put too much effort into acquiring it. One way to do this is to use Page Authority.

Page Authority is another Moz metric that is very similar to Domain Authority, except that it only applies to a single page rather than an entire domain.

The higher the Page Authority of the page you want a link from, the more likely it is to help you with your SEO efforts.

We talked about PageRank earlier in this guide and how it helped Google to serve more relevant results to users. Here, we’ll talk a bit more about how it actually works.

PageRank is calculated by Google and based on the number and quality of links pointing to a web page. It runs on a scale from 0–1, with 1 being the highest. Google assigns a PageRank score to every page that they index and rank in their search results. It’s ever-changing and updated in real time.

We used to be able to get a rough idea of what the PageRank was for a particular page by using the Google Toolbar. However, Google stopped updating this back in 2016, which means that we can no longer use it as a metric to measure how powerful a link may be.

Despite this, PageRank is still used internally by Google and appears to still play a big part in their search algorithm. It has no doubt evolved a lot over the years, but you can read about the earlier version here.

We've already covered the meaning of anchor text; now let's consider what it means as a way of assessing the impact of links for SEOs.

Anchor text can give Google an indication of the subject matter of the page being linked to. So if I linked to a page using the words "fitness routine," then it’s likely that the page being linked contains information about fitness routines. Google can then use this information as part of its ranking algorithms. In this case, they may decide that the page being linked to should rank higher for the keyword "fitness routine" and close variations. John Mueller confirmed that they can use anchor text in this way during this SEO office hours video.

For many years, having a lot of links pointing to your website that contained your keyword as the anchor text was a very good way of helping you rank well for that keyword. While this is still the case to some extent, it does appear that the strength of anchor text as a signal is diminishing slightly. This is most likely because of the over-optimization of anchor text by SEOs, and Google's readiness to penalize such websites through the Penguin update.

Due to the changing nature of the perception and use of anchor text, it’s probably best to be cautious when building links. Try not to build too many links that have the exact same anchor text in them, particularly if the links are not of the highest quality, such as links that are from low-quality domains, non-editorial sitewide links, or links that have too much anchor text. You should try to make your link profile look as natural as possible, which often means getting links that use your brand or company name as the anchor text.

When link building, you’ll obviously want to keep track of how many links you’ve built. You’ll also want to check into how your website compares to your competitors' sites, to see how far (or how far ahead!) you’ve gotten.

As we've discussed in previous chapters and seen in surveys, the raw number of links pointing to your website is seen as a strong ranking signal. However, you do need to remember that the quality is equally, if not more important than the number.

As a metric, number of links can be useful to us in two main ways:

1. Measuring progress / success of a link building campaign

2. For running comparisons between your website and competitors' sites

Both of these uses still need to factor in quality of links in order to be helpful to us. When we compare our number of links to a competitor's number, it can sometimes show gaps that may explain ranking differences. If you're trying to rank for the keyword "wooden tables" and the websites on the first page of results all have over 1,000 links, that gives you a solid sense for the competitiveness of that niche and the kind of attention you need to earn in order to rank among those results.

Not to be confused with the raw number of links, linking root domains is an even more powerful ranking signal to Google. When we say linking root domains, we mean the number of distinct domains that link to us, not the raw number of links.

You can see the difference between linking root domains and total inbound links in Link Explorer:

For example, if CNN linked to you from five different news stories, that would be counted as five links, but only one linking root domain, since all five links came from cnn.com.

If the BBC linked to you from one news story, that would be one link and one linking root domain.

The number of linking root domains is a stronger signal than the raw number of links because it is a better indication of the true popularity of a website. If we go back to how Google thinks of links as "votes," then in this sense each website has only one vote to give you. No matter how many times they link to you, they still only count as one vote. This isn’t necessarily a bad thing, but there may be a point of diminishing returns when getting links from the same domain over and over.

Multiple links from the same domain can be the result of a number of things. Linking from multiple content pages is one way, but the most common ways are by what we call sitewide links. A sitewide link is a link that is placed in some kind of templated element of the website, such as the header, footer, or sidebar. The most common example is a "blogroll" link, as a blogroll is generally on every page of the website.

In general, these types of links are not as valuable as in-content links from just a few pages. Sitewide links can sometimes be spammy, paid for, and not editorially given in the sense that Google would like. Therefore, you should treat them with caution, only get them from high-quality websites, and don't be too aggressive with your anchor text.

There has always been some debate as to whether relevance is a strong signal used by Google to calculate the value of a link. Logic tells us that it should be, because it’s natural for relevant websites to link to each other. However, what if you get a link from the homepage of the BBC to your website about coffee? You wouldn't reject it just because the BBC website isn't about coffee.

If we look beyond link building for a moment though, you still want to bring targeted traffic to your website so that you can try to convert visitors into customers. For this reason alone, you should be trying to place links on websites where potential customers may visit. This means that the value of the link goes far beyond SEO and can become a source of direct income.

As discussed in the anchor text section above, there are some indications that Google is moving away from anchor text as a strong signal and, instead, could be using analysis of an entire page to attribute relevance to the link. If this proves to be the case, then getting links from relevant pages could become a strong ranking signal.

Right now, best practice should be to focus on quality to make sure you're being passed link equity and on relevance in the sense that you want to attract the right kind of traffic.

Imagine you live in Seattle and you have a blog about coffee. You're going to share a link with your readers to the website of a local coffee shop that serves the most amazing fresh coffee ever. Where would you place this link on the page?

If you really wanted your readers to see it, you'd position it somewhere obvious. Probably in the main body of the page, probably near the top of the page, and probably within some content that explains how amazing the coffee shop is.

You probably wouldn't place the link in the footer, right? Many users may not scroll down the page that far, and even if they do, they wouldn't expect to find useful links in that section.

Google is able to work out the position of a link on a page, and from this could choose to value it differently. If the link is in the footer of a page, then Google could reduce the value of that link because they assume it isn't a great link for users (otherwise, it wouldn't be hidden away in the footer).

Google can also use the position of links on a page in aggregate. For example, they could see if 50% of all the links pointing to your website are in some kind of footer. This could indicate low-quality link building, and Google may decide to take a closer look.

Another example could be if Google finds that 50% of the links pointing to your website are from sidebars. Again, on its own, this may be legitimate, but it could also be a signal to Google that you're buying links. Many link brokers will place links in the sidebar of pages as opposed to within the content.

Because of this ability, you should make sure that you are getting links from websites which are happy to link from within content wherever possible. There is nothing wrong with the odd sidebar link, but too many of them does not signal a good link profile.

You made it! That was The Beginner's Guide to Link Building!

I hope that you’ve enjoyed learning more about link building and now feel that you’re in a position to approach link building in an effective and efficient way.

To conclude, I’d encourage you to really think about the long-term benefits of link building (and SEO generally) throughout your work and avoid the temptation to take short-cuts. I’d also encourage you to really think hard about how you make the websites that you work on link-worthy and able to attract links that you didn’t ask for. Investing time into this now will help you massively long-term and set your website up for success at a time when the online world is only going to become more competitive. Google is also clear in that they only want to reward websites that truly deserve to rank well in their search results.

Skate to where the puck will be.

Further reading

If you’d like to read more about link building, here are some places that you can start:

• The Moz Blog category on link building

• The Moz Learning Center on link building

• The Moz guide to local link building

• The Link Building Book by Paddy Moogan