In the search engine optimization world, no topic gets talked about more than backlinks.
I. Mean. None.
Don't believe me? Let’s take a look:
Well, except for one thing: link building, which is the process of acquiring more backlinks.
Bottom line: backlinks rule the SEO world.
In this article, we’re going to show you why.
- How backlinks benefit your SEO
- How Google used backlinks to start…Google
- What separates a quality backlinks from a sh*t link
- Why the number of backlinks isn’t everything
- How to monitor your backlinks
- How to work backlinks into your SEO strategy
Are you ready?
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What is a backlink?
A backlink is a hyperlink from someone else’s website back to yours. When a visitor clicks on a backlink to your website, it will take them from someone else’s website to your website.
For example, this is a backlink from Shopify to us, using the anchor text “KlientBoost:”
You can backlink to other websites too. For example, if you external link to another website, that counts as a backlink for whomever you link to.
Another example is this external link from our SEO keywords article to Google. In this example, Google gets the backlink.
In SEO, we sometimes refer to backlinks as inbound links, incoming links, or usually just “links.”
Whatever you call them, backlinks are widely considered the holy grail of search engine optimization.
How do backlinks benefit SEO?
Backlinks are one of Google’s top three ranking factors, alongside relevant content and RankBrain.
This is huge considering that Google uses 200+ ranking factors in their algorithm.
For Google and other search engines, backlinks function as votes of confidence. If other credible websites link to yours often, there’s a good chance you’re also a credible website with high-quality content.
Think of it this way: Google values relevance and authority more than anything.
Relevance deals mostly with the content on your website (on-page SEO). In other words, is your content relevant to a searcher’s query?
To build authority (off-page SEO), Google wants to know that other reputable and relevant websites also value your information. They find that out by measuring how many of those websites cite your work with a backlink.
Without backlinks, you can have the best, most relevant content in the world, but it will never make it to the top of a competitive search engine results page (SERP) without authority to boot.
Bottom line: the more links you have from high domain authority websites (trusted, reputable, relevant), the better chance you have of ranking.
The origin of backlinks (PageRank)
To help you understand just how important backlinks are to SEO, know that in 1998, Larry Page and Sergey Brin founded Google with the underlying assumption that the most important websites online were likely to receive more links than other websites.
Backlinks were literally in their thesis for a better search engine.
They called their algorithm PageRank. PageRank could count the number and quality of links pointing to each website, then rank those websites based on who had more and better.
Fast forward 20+ years and Google still uses a version of PageRank (along with other signals):
Backlinks have been the gold standard for search rankings since Google's inception in 98’.
But it hasn’t always been smooth sailing. In its infancy (and well into the 2000s), PageRank was easy to manipulate (see: blackhat SEO).
You could simply buy hundreds of backlinks from link farms or private blog networks, or spam comment sections with links to your website, and violà: page one rankings.
In 2012, Google launched the Penguin Update (and subsequent Penguin updates up until 2016): a dramatic update to their core PageRank algorithm that would better identify, devalue, and/or penalize link spam, link schemes, and low-quality links.
Today, backlinks still reign supreme. Only now, in the post-Penguin era, you need high-quality, natural backlinks, not manufactured ones.
What makes a good backlink?
Not all backlinks are created equal.
When analyzing link quality, look for the following:
3. Referral traffic
6. Rich anchor text
Links, whether internal or external, function like highways for people and search engines.
Not only do they pass visitors from one page to the next, but they also pass authority (aka “link juice”) from one page to the next. The higher the domain authority of the linking root domain, the more value the backlink will pass to your website.
What’s domain authority (DA)? Though not a ranking factor, domain authority is a metric invented by Moz that scores websites and web pages based on the quantity and quality of their links. In essence, it’s like a back-engineered version of PageRank (though not nearly as sophisticated or complex). It makes a great proxy for measuring authority of links.
Higher DA websites correlate with higher rankings. And links from higher DA websites help rankings more than links from lower DA websites.
For example, a backlink from Wikipedia.org (DA 98) will boost your rankings more than a backlink from DrunkElephant.com (DA 60). (Though both would be great.)
You can easily find the domain authority of a website (i.e. link authority) using Moz’s free Mozbar Chrome extension:
Simple: If you’re a landscape business, a link from a fitness blog is not topically relevant to your domain of expertise like a link from FineGardening.com.
Links from topically relevant websites are more valuable because they help Google better understand what your website is about.
How? Search engines use knowledge graphs (read: semantic SEO) to understand the relationships between things online. Think of a knowledge graph like a web of connected information.
Well, Google knows that a link from an article about landscaping to a landscaping website is relevant and belongs within the same knowledge graph. Just like they know that an article that talks about weight lifting doesn’t belong in the same knowledge graph.
Also, Google likely uses their patent (designated as the “Reasonable Surfer” patent) to value links from topically relevant websites more than those that aren’t.
Bottom line: don’t confuse Google about what your website is about. Aim for links from relevant websites.
3. Referral traffic
Forget about Google for a minute. If your purpose of acquiring backlinks is solely to rank web pages higher in Google, you’re missing the point.
Doesn’t it make more sense to acquire backlinks from topically relevant websites that also send referral traffic made up of your ideal customers?
But data suggests that links from sites that pass traffic might also boost rankings more.
An Arehfs study found a correlation between backlinks from sites with organic traffic and higher rankings.
4. Unique linking root domain
A “linking root domain” refers to the “root” domain that links (as in the home page URL), not the slug of the linking page.
For example, if www.klientboost.com/seo/duplicate-content links to another website, the linking root domain is klientboost.com, not the /seo/duplicate-content part.
It’s common for the same linking root domain to link to a specific website more than once. Actually, it’s super common.
According to Ahrefs, 80% of websites link to the same website more than once:
But multiple links from the same site don’t carry as much weight as a new link from a new linking root domain. According to research from Brian Dean of Backlinko, more links from the same domain have diminishing returns:
Let’s look at a real world example.
We get 281 total backlinks from CXL.com.
CXL is an incredible domain that’s topically relevant and sends relevant referral traffic to our website. So it’s not that multiple links from CXL aren’t valuable (they are). Nor are we encouraging you to stop at acquiring one backlink from the same domain (once you get one, two becomes easier).
But in terms of pure backlink value, acquiring a new high domain authority link from a new website will help boost your rankings more than acquiring a second link from the same website.
This one is simple.
Gone are the days of spammy comment links, site-wide footer links, links with awkward anchor text jammed into the middle of a sentence, or links from link farms.
Today, if you want to avoid a Google penalty (like the one below), it’s best to acquire natural links with natural placement from websites that link out naturally.
6. Rich anchor text
Anchor text is the actual text used in the backlink. For example, in the link Google's Search Quality Guidelines, “Google’s Search Quality Guidelines” is the anchor text.
Anchor text can come in all shapes and sizes. For example:
In the early days of Google, PageRank used anchor text as a strong ranking factor (you can read about it in one of Google’s early papers here).
More specifically, they weighted exact-match anchor text (links that used the exact keywords in the anchor text) heavier than generic anchor text (e.g. “here” or “read more”).
But like everything else, SEO specialists caught on and started gaming the algorithm by building hundreds of exact-match backlinks, whether or not it was good for the user experience (and in most cases, it wasn’t).
In fact, one of the primary reasons Google launched their Penguin Update (mentioned earlier) was to combat spammy anchor text.
Fast forward to 2021, and where does Google stand with anchor text? Do they still use anchor text when ranking websites?
“…the better your anchor text is, the easier it is for users to navigate and for Google to understand what the page you’re linking to is about.
With appropriate anchor text, users and search engines can easily understand what the linked pages contain.“
And from Google’s John Mueller:
“If you’re updating anchor text internally to make it more easily understandable by users then usually that also helps search engines to better understand the context of those pages. So I would definitely go for that.”
Bottom line: Google still uses backlink anchor text to better understand what a page is about. Although you can’t game the algorithm like you could in the past, descriptive anchor text (that's good for the user first and foremost) can help your page rank.
Last, a good backlink can be easily crawled by search engine spiders. Which means it’s a “dofollow” link as opposed to a “nofollow” link.
What the heck is dofollow/nofollow?
A dofollow link is a link that web crawlers can follow and pass link authority through.
Good news: links, whether internal or external, come “dofollow” out of the box. You don’t need to specify anything in the HTML code.
A nofollow link, on the other hand, has a piece of HTML inserted into the link attribute that tells search spiders not to crawl the page or pass along link authority.
For example, this is what a dofollow link looks like:
And this is what a nofollow link looks like:
<a href="https://www.w3schools.com/" rel= “nofollow”>KlientBoost</a>
When it comes to backlinks, nofollow links can still drive traffic. And if it’s traffic that buys or subscribes, who cares if it doesn't help rankings. But for it to help rankings, the backlink needs to be dofollow.
What makes a bad backlink?
Pretty much the opposite of what makes a backlink good. But here are five types of links to be aware of:
- Purchased links
- Irrelevant links
- Sitewide links
- Press release links
- Blackhat links
1. Purchased links
You can purchase a backlink from pretty much anywhere. Heck, you’ve probably had a link farm reach out to you via cold email and ask if you were interested in their DA40+ backlinks for $100 each.
Too bad Google has cracked down significantly on paid links.
Google gets spam links reported by normal people, they have a manual spam team that checks for paid links, and they've improved their algorithms so dramatically that they can detect unnatural link practices and raise a red flag internally.
Resist the urge. Don’t do it.
Note: sponsored links are different. You can pay for sponsored links as long as the platform designates that the link is sponsored either by nofollowing it or by using the rel=sponsor attribute.
2. Irrelevant links
A link from a high domain authority website that has nothing to do with your industry or topical expertise is irrelevant.
It won’t send targeted referral traffic to your website.
It won’t count as much in the eyes of Google’s algorithms.
It’s purely a play to improve rankings.
3. Sitewide links
A sitewide backlink is a link that points to your website from a footer, header or sidebar that appears on every page of another website.
Back in the day, sitewide links were common because SEO specialists wanted to game the algorithm. “If we put a link in the footer, we’ll get thousands of links, not just one.”
But today, when Google sees you have 3,576 backlinks pointing to the same page from the same website, that raises a red flag.
If you don’t get hammered with a Penguin penalty, Google isn’t going to weigh all those links the same.
Not all sitewide backlinks are bad though.
There are perfectly good reasons why you might have a sitewide backlink. For example, if you’re a web development company or template creator and place “WordPress template created by WPTemps.com” in the footer of one of your free sites, you’re likely in the safe zone. Just don’t seek out sitewide links in an attempt to trick Google. It won’t work.
4. Press release links
SEO specialists used to spam press releases with dozens of links, then syndicate those press releases across hundreds of press release distributors.
But in 2013, Google updated their webmaster guidelines, stating that press release links should be nofollowed, and that press releases were similar to advertisements in the eyes of Google algorithms.
5. Blackhat links
Last, any backlink that wreaks of manipulation, like automated blog comments with links, links from private blog networks (thousands of websites that link to each other), or links from websites with high spam scores.
Tip: Before reaching out for a backlink, or if you want to check the quality of an existing backlink, run the domain through Moz’s free domain analysis tool. Check for high domain authority and low spam scores.
And if you discover spammy backlinks pointing to your website, Google recommends reaching out to the webmaster to have them removed, or disavowing them using Google’s disavow tool within Search Console.
How to monitor backlinks
You can monitor your backlinks using any number of SEO tools. Or you can use Google’s free Search Console tool.
Let’s explore Search Console first. Then we’ll explore some of our favorite backlink tools.
Google Search Console
First, login to Google search console.
From the dashboard, navigate to the “Links” tab to the bottom left:
From there, you can view internal links, external links, and backlinks (“Top linking sites”):
From there, find your backlinks under “Top linking sites”:
Last, you can drill down by clicking on the linking root domain. From there, you can see exactly what page(s) they link to.
Then there are backlink checker tools. And, oh my, are there tons of them.
Why would you pay for tools to check backlinks when Google shows you for free?
Because paid tools come with loads of other data that make link monitoring and link building way easier.
For example, here are some common features of a paid link tool that you can’t get with Search Console:
- Organic traffic of linking sites
- Domain authority of linking sites
- Historical data of linking sites
- Analyze new vs. lost links
- Find broken backlinks
- Analyze competitors backlinks
- Audit your backlinks for quality
Lucky for you, we wrote an entire article on SEO tools here.
But here are three of our favorites:
How to get more backlinks
Sometimes you earn links organically. Sometimes you build them manually.
For example, a blogger may love your article and link to it from theirs (earned). Or you may build business profiles on business directories that also include backlinks (built).
The grey area in between is massive. There’s virtually endless ways to acquire backlinks.
Good news: we wrote an entire article about link building.
But let’s explore the two primary ways to get more links here.
Acquire links organically
We have over 30K links from over 3K referring domains and we only built a handful of them. Almost all of them have come organically because our content kicks ass. (We’ve also worked really freakin’ hard on a lot of our content over the last six years.)
Just remember: If you build it, that does not mean they (backlinks) will come.
Link-worthy content still needs eyeballs on it. This means your linkable assets need distribution of some sort, whether paid, shared, or via search engines.
Acquire links by building them
Then there’s link building, or the intentional process of building one-way links to your website using various tactics.
You can build links on forums, directories, industry websites, or social media profiles.
Or you can build backlinks by reaching out to other authority websites and asking them for a link.
Building backlinks through outreach is a lot like public relations—it takes a linkable asset worth linking to, research, outreach, persistence, and some form of a persuasive pitch to get someone to link to your website for the first time.
But done right, and you can amass quite the backlink profile over time.
Common backlink building tactics include:
- Guest posts
- Content marketing
- Broken link building
- And so many more
We’d dive deeper, but we explore link building strategies and tactics in its own article here. Check it out.
There’s a reason backlinks are the most talked about topic in SEO: there’s no other factor that influences ranking more.
When building or earning your own backlinks, remember the first principles of good links:
- Good links come from authority websites
- Good links come from relevant websites
- Good links send referral traffic (like, real people)
- Good links are come from new domains
- Good links come naturally, not spam-ally
- Good links use rich anchor text naturally
- Good links are followable links