Backlink: What It Is and How to Earn Good Ones

A backlink is a link on another website that points to a page on your website. If a trade publication links to your pricing guide, that link is a backlink to your site, and to the publication it is an outbound link. People also call these inbound links or external links.

Backlinks are one of the oldest ideas in search. They help search engines find new pages, understand what those pages are about, and judge which pages other people consider worth pointing to. They also shape how often your brand shows up in the sources that AI assistants read and cite.

What is a backlink?

A backlink is any hyperlink from a page on one domain to a page on a different domain. The page that holds the link is the "linking" or "referring" page, and the site it lives on is the referring domain. The clickable words in the link are the anchor text.

Not every link carries the same meaning. A link inside a thoughtful article that recommends your guide says something different from a link in a forum signature or a paid ad. Search engines try to tell those apart, and site owners can label some links with attributes such as nofollow, sponsored or ugc to describe the relationship.

The idea goes back to Google's founding. In their 1998 paper on the Google prototype, Sergey Brin and Larry Page described ranking pages higher when many other pages point to them, treating links much like academic citations.

Why backlinks matter

Backlinks matter for three practical reasons: discovery, understanding and trust.

Discovery. Google finds many new pages by following links from pages it already knows. Its How Search Works guide explains that pages are discovered when Google extracts a link from a known page to a new one. A link from a site Google crawls often can help a new page get found and moved toward indexing.

Understanding. Google's guide to its ranking systems says its link analysis systems look at how pages link to each other to work out what pages are about. It also confirms that PageRank, the original link-based system, has evolved a lot and is still part of its core ranking systems.

Trust and visibility in AI answers. Generative tools like Google's AI Overviews, ChatGPT search and Perplexity pull from pages that rank well and from sources the web already references. A brand that earns links from respected publications tends to appear in more of the places these systems read. Links are not the only factor, but a page nobody references is harder for any system to find or trust.

Keep this in proportion: Google's own SEO Starter Guide says there is much more to Search than links. Helpful content still comes first.

How backlinks work

Crawling and following links

Google's crawler generally follows standard HTML <a> elements that include an href attribute. Its link best practices note that links built only from script events or non-standard tags may be missed. A backlink that is hidden behind JavaScript click handlers may not count for much because it may never be seen.

Link attributes

Site owners can describe a link with a rel attribute. According to Google's guidance on qualifying outbound links, rel="sponsored" is for paid placements, rel="ugc" is for user-generated content like comments, and rel="nofollow" is the fallback when you don't want to be associated with a page. Google says links with these attributes will generally not be followed, which means the attributes act as guidance rather than strict commands.

Context and relevance

A link's surroundings matter. The anchor text and nearby words tell readers and search engines what to expect on the other side. A link from a page about bookkeeping software to your accounting template is naturally more relevant than a link from an unrelated gambling blog.

Quality signals and spam detection

Because links can influence rankings, people have tried to fake them for decades. Google runs spam detection systems, including SpamBrain, to catch behavior that violates its policies. Its spam policies define link spam as creating links mainly to manipulate rankings, and they list examples such as buying links, excessive link exchanges and automated link building.

Backlinks in practice: a simple example

Picture a hypothetical regional HVAC company that publishes a clear, original guide to heat pump rebates in its state, including the steps to apply and a list of eligible equipment. A local news site writing about energy costs links to the guide as a helpful resource. A homeowners' association newsletter does the same. A trade association adds it to its resources page.

Each of those is a backlink. None was bought or traded. Over time, those links help search engines discover the page, connect it to the topic of heat pump rebates, and see that relevant local sources point to it.

Now picture the opposite. The same company buys 500 links from a network of unrelated blogs, all using the exact phrase "best HVAC company." That pattern matches several examples in Google's link spam policy. At best, the links are ignored.

How to earn quality backlinks

Publish something worth citing. Original data, clear explanations of confusing topics, free tools and well-organized guides attract links on their own.
Make linkable pages easy to find. Use descriptive titles and clean URLs so people know exactly what they are linking to.
Do real outreach. Tell relevant writers and site owners about a resource that genuinely helps their readers. Keep it short and personal.
Use digital PR. Newsworthy stories, expert commentary and data releases can earn coverage from publications. These mentions often come with links and build brand recognition even when they don't.
Reclaim unlinked mentions. When someone mentions your brand without linking, a friendly note asking them to add a link often works. Read more about brand mentions and why they matter for AI visibility.
Fix broken links pointing to you. If other sites link to pages you've deleted, redirect those URLs to the closest relevant page.
Qualify paid placements. If you sponsor something and get a link, it should carry rel="sponsored" or rel="nofollow". Google's policy says paid links are fine for advertising when qualified this way.
Monitor your profile. The Links report in Google Search Console shows top linking sites, top linked pages and top linking text. Google's help page for the Links report notes it shows a sample, not every link.

Common backlink mistakes and myths

Chasing quantity over relevance. A handful of links from respected, relevant sites usually beats hundreds from low-quality directories. Google's spam policies specifically call out low-quality directory and bookmark links.

Over-optimized anchor text. Guest posts, advertorials and press releases that pass ranking credit with keyword-stuffed anchors are listed as link spam examples. Natural link profiles use a mix of brand names, URLs and descriptive phrases.

Assuming nofollow links are worthless. They can still send real visitors, build awareness and lead to followed links later. They just aren't meant to pass ranking credit in the usual way.

Treating third-party metrics as Google's. Scores like Domain Authority or Domain Rating come from SEO tool vendors. They can be useful for comparison, but Google does not use them.

Thinking links can fix weak content. Links help good pages get found and trusted. They rarely rescue a page that doesn't satisfy what searchers want.

Backlinks vs. brand mentions

A backlink is a clickable link. A brand mention is any reference to your company, product or people, linked or not. Both matter, but in different ways. Backlinks feed link analysis systems and send referral traffic. Unlinked mentions still help people, and potentially AI systems, associate your brand with a topic. Strong programs aim for both.

How Butter approaches backlinks

At Butter, we treat backlinks as a reputation project, not a volume game. Before Butter, our founder spent 11 years growing a SaaS marketing program and built and sold an SEO agency, and the lesson that stuck was simple: the links that last are the ones a real editor would choose to give.

Every Butter plan includes link work. The GEO plan includes one AI-crawlable content citation and backlink each month, along with off-page recommendations. The GEO+SEO plan adds one quality backlink each month on top of on-page optimization and technical SEO fixes, so the pages earning links are also crawlable and well structured. For brands that want more coverage, our Public Relations add-on focuses on earned media.

We don't buy links from networks, and we don't promise a specific number of placements will move a ranking. If you want to see how links fit with the rest of your search program, our SEO service page lays it out.

Frequently asked questions

How many backlinks do I need to rank?

There is no set number. Google does not publish a threshold, and the right amount depends on your competitors, your topic and the quality of your content. Focus on earning relevant links from respected sites rather than hitting a count.

Are nofollow backlinks useful?

Yes, in practical ways. They can drive referral traffic, raise awareness and lead to other people linking to you. Google says it generally does not follow them, so they are not a reliable way to pass ranking credit.

Can bad backlinks hurt my site?

Google's systems are designed to detect and neutralize spammy links, and most random low-quality links are simply ignored. Problems are more likely when a site actively participates in link schemes, such as buying links that pass ranking credit.

Do backlinks help with AI search visibility?

They can help indirectly. AI search features often draw on pages that rank well and sources the web already references, and links support both. No one can guarantee placement in AI answers, so treat links as one part of a broader visibility strategy.

Sources and further reading

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