Backlinks are especially valuable for SEO because they represent a “vote of confidence” from one site to another.

In essence, backlinks to your website are a signal to search engines that others vouch for your content. If many sites link to the same webpage or website, search engines can infer that content is worth linking to, and therefore also worth surfacing on a SERP. So, earning these backlinks can have a positive effect on a site’s ranking position or search visibility.

Earning and giving backlinks

Earning backlinks is an essential component of off-site SEO. The process of obtaining these links is known as link earning or link building.

Some backlinks are inherently more valuable than others. Followed backlinks from trustworthy, popular, high-authority sites are considered the most desirable backlinks to earn, while backlinks from low-authority, potentially spammy sites are typically at the other end of the spectrum. Whether or not a link is followed (i.e. whether a site owner specifically instructs search engines to pass, or not pass, link equity) is certainly relevant, but don’t entirely discount the value of nofollow links. Even just being mentioned on high-quality websites can give your brand a boost.

Just as some backlinks you earn are more valuable than others, links you create to other sites also differ in value. When linking out to an external site, the choices you make regarding the page from which you link (its page authority, content, search engine accessibility, and so on) the anchor text you use, whether you choose to follow or nofollow the link, and any other meta tags associated with the linking page can have a heavy impact on the value you confer.

Competitive backlink research

Backlinks can be time-consuming to earn. New sites or those expanding their keyword footprint may find it difficult to know where to start when it comes to link building. That’s where competitive backlink research comes in: By examining the backlink profile (the collection of pages and domains linking to a website) to a competitor that’s already ranking well for your target keywords, you can gain insight about the link building that may have helped them. A backlink tool like Link Explorer can help uncover these links so you can and target those domains in your own link building campaigns.

Not all backlinks are created equal. Here are some of the many attributes that contribute to a backlink’s quality and utility.

Relevance

Google places more value on relevant backlinks because people are more likely to click on them. This is something they talk about in their “reasonable surfer” patent. What does this mean in real terms? If a plumber has backlinks from two pages, one about cats and one about installing boilers, chances are the latter is most valuable. This idea also plays out at the domain level.

Authority

Backlinks from strong web pages usually transfer more “authority” than those from weak ones. Page-level authority is something we’ve studied a few times, and we’ve found a clear relationship between it and organic traffic. Google’s original patent states that authority is split equally between all outbound links on a web page. So if you have backlinks from two pages and one has more outbound links than the other, then, all else being equal, the link from the page with fewer outbound links transfers more authority. Are things that simple these days? Probably not. Google has a fair number of patents describing various methods for assigning value to backlinks. Furthermore, internal backlinks also contribute to a page’s authority.

Traffic

Backlinks from high-traffic pages will usually send you more referral traffic than those from low-traffic pages. That’s obvious. The real question is whether backlinks from high-traffic pages positively affect rankings more than those from low-traffic pages? There’s a small but clear correlation between rankings and backlinks from pages with organic search traffic. However, the sheer number of backlinks from unique websites (referring domains) and page-level authority look to be more important.

Placement

Because people are more likely to click prominently-placed links, some links on web pages likely pass more authority than others.

Followed vs. nofollowed

Nofollowed backlinks don’t usually influence the linked page’s rankings—although they can. Because link building takes time and effort, it’s best to prioritize getting followed links. Just don’t kick up a fuss if you get a nofollowed link. It may still have some SEO value.

There are two ways to check a website or web page’s backlinks. The first method only works for sites that you own. Use the second to check backlinks to another website or web page.

Checking backlinks in Google Search Console

Google Search Console gives you data about your website’s organic search traffic and overall performance. It’s free to use—just sign up for a free account and verify ownership of your website.

Checking backlinks using a third-party backlink checker

To check backlinks to a website that you don’t own, use a tool like Ahrefs’ free backlink checker.

Earning backlinks

This is when people discover your content via search engines like Google, social media, or word of mouth, and choose to link to your page. In order words, earned backlinks are organic seo . You can improve your chances of earning more backlinks by creating truly useful content that people should want to link to.

Creating backlinks

This is when you manually add links to your site from other websites. Examples include submitting to business directories, leaving blog comments, and replying to forum threads. Backlinks are important when it comes to ranking in search engines like Google. That said, not all backlinks are created equal. Relevance, placement, and other attributes all contribute to a link’s quality and utility.

As a general rule of thumb, the easier it is to get a link, the less valuable it’ll be.