The complexities of SEO can essentially be whittled down to two main categories. 1) On-site optimization involves placing quality content throughout your site, including relevant keywords within that content, and making pages easily accessible to search engines. And, 2) off-site optimization focuses on strengthening your website through inbound links and mentions on other websites.
Search engines look at a wide variety of factors when determining rankings and both on-site and off-site optimization are need for success, but links are arguably the most important factor and can have a huge impact on your SEO results.
Each link carries with it a range of factors that can affect how that link drives SEO value and which keywords it will be most helpful for.
Here are 10 aspects of a link that are important to understand:
Follow vs. Nofollow
To understand follow and nofollow links, we first need to understand the importance of a link when it comes to SEO. In short, links are important because search engines view them of votes of confidence in the popularity and authority of your website. The more links you have pointing to your site from other high quality, relevant websites, the more likely you are to rank for your target keywords.
Unless otherwise indicated, most links you’ll come across will be “follow” links. This means search engines will count the SEO strength passed by the link when determining rankings.
However, in some cases, a website will choose to label an outbound link as “nofollow” which tells search engines not to consider this link when evaluating the SEO strength of a site
“Nofollow” links are primarily used to combat spam. For example, Wikipedia sets all outbound links from their domain as “nofollow” so spammers won’t flood the Wikipedia site with fake articles just to get a valuable link. You’ll often come across “nofollow” links in forums and blog comments as well.
This doesn’t mean that “nofollow” links are worthless. It’s very possible that a “nofollow” link from a forum or a widely used knowledge base like Wikipedia can still drive a ton of traffic to your site and strengthen your brand.
Anchor text is the actual words that make up the link. For example, in the following phrase the anchor text is “internet marketing agency”:
Pronto Marketing is an internet marketing agency for small businesses.
To be a bit more specific, this is what the HTML of a link looks like:
Anchor text is important to understand for SEO because search engines look at the words used in the anchor text of links pointing to your site to help determine what the page being linked to is about.
So if a page receives inbound links with “internet marketing agency” as the anchor text, that page is more likely to rank in search results when someone searches for that phrase.
However, it’s important to note that too many links with the exact same keyword-rich anchor text can be a sign to Google that you’re attempting to manipulate the search results through link building. So if you’re targeting keyword-based anchor text, make sure to keep them varied.
You can find much more detail about the importance of anchor text in this great article from Moz.
When search engines are evaluating a link to your site, they don’t just look at the words in the anchor text of the link, but they also look at the content of the entire page and domain linking to you.
Again, these are signals for search engines to help determine what keyword phrases your page should rank for and a link from a relevant website in your industry is going to provide more targeted data for search engines analyze.
This doesn’t mean that all links from irrelevant sites are worthless. It’s very common to receive links from websites that aren’t directly related to your business. These might be news sources, businesses in other industries that you’ve partnered with, or a blog article with a tangential interest in your industry.
For example, on prontomarketing.com we have links from many marketing related sources, but we also have links from a Thai newspaper, the website of our HR systems provider, a blog article about a local charity we work with, and many more that aren’t directly related to marketing. These links are definitely still work acquiring.
The main thing to be careful of is links from sites that both irrelevant and spammy. More on this a bit later.
PageRank is a measurement of the SEO strength for a given page. It’s the algorithm that first put Google on the map and is a complex equation that takes into account the number of links pointing to a page as well as the strength of the pages linking to it.
Since Google first launched the PageRank algorithm back in the 1990s, it’s evolved to become even more sophisticated. In the last couple of years, Google has stopped providing public PageRank data for websites, so it’s no longer a great measurement of link strength. However, other metrics like MozRank and Page Authority can serve as a replacement.
In general, a link from a page with higher PageRank (or MozRank/Page Authority) will be more beneficial than a link with lower PageRank.
With that said, page-level link metrics aren’t always a great indicator of which pages you should try to acquire links from. One main reason is that you’ll often obtain links from pages that have not been published yet - such as a guest blog article on another website. In those cases, the strength of the overall domain is much more important.
Domain Authority (DA) is a measurement of the overall SEO strength of an entire domain. Moz provides a numerical metric for this to help you judge the link authority of a site. As with PageRank/Page Authority, links from a website with a higher Domain Authority will, in general, be more beneficial, than links from a lower DA site.
However, there are some non-data aspects to this as well.
You might want to consider how authoritative or influential the site is within your industry or throughout a wider audience. For example, if a new start up gets mentioned and linked to in a TechCrunch article, not only is the link very valuable from an SEO perspective, but it also gives the start up a lot of credibility. It’s something they could even brag about on their website with an “As seen on” section.
On top of all of this, websites with high Domain Authority also tend to receive a lot of traffic. This means a link from a high DA site will reach a wider audience and will help spread awareness of your brand. It also means more traffic coming to your site through the link itself.
Existing inbound links from the linking domain
In general, having a wider variety of domains linking to your site will have a larger impact of on performance. If we go back to the links as votes of confidence metaphor, votes from different domains are more powerful than multiple votes from a single domain. So if you already have a link from a website, getting a second link from that site will be a little less powerful.
With that said, if you come across a high quality website that you can obtain multiple links from (through regularly guest blogging for example), definitely jump on that opportunity - building a close association with a well-established website is great for the way search engines will view your site.
Location on the linking page
This used to have a much higher impact than it does today. Search engines used to give more weight to links that appeared higher on the page. That isn't so much the case today but there is one big exception: site-wide links pointing to your website.
Site-wide links (meaning links that can be found on every page of a website) can generally be found in the footer or sidebar of a website. These aren't inherently bad but if not handled appropriately, they can be a clear sign to search engines that you're trying to manipulate search results through link building.
You'll often see site-wide links in the footer of a website with something like "Website powered by [Company]". The best way to handle these is to make sure they have a “nofollow” HTML tag included with them which tells search engines to exclude that link when determining the link strength of a website.
It's uncommon that you'll receive site-wide links without your knowledge, but if you manage websites for your clients or develop applications with outbound links, it's important to understand the SEO impact of the links you create.
Number of other outbound links on linking page
One of the ideas included in PageRank and other link analysis metrics is that the more outbound links a page has, the less SEO strength it passes through each link.
Here’s an oversimplified example: if a page has a Page Authority of 10 and has 5 outbound links, each link would pass a Page Authority value of 2. If the same page had 8 outbound links, each link would pass a value of 1.25.
It’s much, much more complicated than that, but the general idea still applies. The main place you want to watch out for this is on pages that have hundreds of outbound links. Links to your site from pages like this likely carry very little SEO strength. These pages also tend to be on the spammier side so a link from them can end up having a negative impact on your site’s performance.
Quality of other outbound links on linking page
When you obtain a link, take some time to look at the other pages being linked to from that page. If it’s a blog article, you might notice that the author has linked to a few other resources that the reader might find helpful. If these resources are highly authoritative in search engines’ eye, they’ll start to associate that authority with your site as well.
On the other hand, if the other sites being linked to are low quality or spammy, search engines will start to equate those characteristics with your site.
Spamminess of linking domain
The two items above are somewhat related to this because along with authority and relevance, they can be clues to help you decide how spammy a page is. Pages filled with low quality, irrelevant content and lots of outbound links to other low quality sources tend to be spammy. Often times, you can judge the spamminess of a page or domain just by looking at it. You can also use data points like Moz’s Spam Score.
It’s natural for a website to receive a few links from spammy domains. To a certain extent, they can’t be avoid because spammy sites tend to add whatever links that want to without any regard for your wishes.
However, they are definitely worth keeping your eye on. Too many spammy links pointing to your site can negatively affect your site’s ability to rank or even end up getting your site penalized by Google. If you’re interested in seeing which website links to your site, check out one of these tools:
It's worth noting that each of these tools has a different process for gathering and filtering link data, so don't be surprised if you see different information for your site on each tool.
Also, where Moz's Open Site Explorer has Page Authority and Domain authority, Aherfs and Majestic have their own authority-based metrics that are calculated in slightly different ways. However, they all have the same goal of helping you determine how authoritative your site is in the eyes of search engines.
Start building links
Ready to build some links to your site? You can find a great list of strategies for building links over at Point Blank SEO. If you’re a Pronto client, we can help with building links to your site. Reach out to our experts to learn more.
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