What Are External Backlinks? An SEO Guide for 2026

External backlinks are links on other websites that point to pages on your site. Google uses them to discover your pages and as a signal of how relevant and useful those pages are, so a few editorial links from respected, relevant sites usually do more for SEO than hundreds of links from directories or link networks.

This guide is for e-commerce and Shopify teams who want to understand how backlinks actually affect visibility in 2026, without the myths. You'll see how external backlinks differ from internal and outbound links, what Google's own documentation says about link attributes and link spam, how to judge a link's quality, a step-by-step process for earning links, and how to keep the ones you have, since published research shows most links eventually disappear.

What are external backlinks?

A backlink is any link from one page to another. An external backlink (also called an inbound link) comes from a different website than the one it points to. If a cooking blog links to your cast iron skillet collection, that is an external backlink to your store.

Every external backlink has three parts that matter for SEO:

• The linking page and site. Who links to you, how relevant they are to your products, and how well linked they are themselves.
• The anchor text. The clickable words. Google's link guidelines ask for anchor text that is descriptive, reasonably concise and relevant to both pages.
• The rel attribute. Whether the link is a normal followed link or carries nofollow, sponsored or ugc, which tells Google how to treat it.

SEO tools count backlinks in two ways: total backlinks (every individual link) and referring domains (the number of unique sites linking to you). Referring domains is usually the more useful number. Fifty links from one site's footer are one relationship, not fifty endorsements.

External backlinks vs internal and outbound links

People mix up three kinds of links. They do different jobs, and you control them to very different degrees.

Internal links are the most underrated of the three. Google's link documentation says every page you care about should have a link from at least one other page on your site. When an external backlink lands on a blog post or guide, internal links are how that value reaches your collection and product pages. Use our internal link checker to find important pages with too few internal links.

How Google uses external backlinks

Google's documentation is short but clear. Its guide to making links crawlable says Google uses links as a signal when determining the relevancy of pages and to find new pages to crawl. Its overview of how Search works says some pages are discovered when Google extracts a link from a known page to a new page.

Discovery

A link from a frequently crawled site gives Googlebot another path to your page. This matters most for new stores, new collections and product launches that have few internal links yet. It does not guarantee indexing; Google still decides whether the page is worth indexing.

Relevance and reputation

Google has never published a weight for links, and correlation studies cannot prove cause. What published data does show is how hard it is to get search traffic without links. In Ahrefs' study of about 14 billion pages in its Content Explorer index, published in December 2023, 96.55% of pages got zero traffic from Google. Ahrefs lists "the page has no backlinks" as one of the main reasons. Of roughly 20 million pages in its index with no referring domains, only 2,997 got more than 1,000 search visits a month.

Read that carefully: pages without backlinks can rank, especially on strong domains and for low-competition queries. But it is rare, and it gets rarer as the query gets more commercial.

Referral traffic

Backlinks are also simply links people click. A mention in a gift guide, a niche forum or a respected review site can send buyers directly, whatever it does for rankings. This is why a nofollow link from a popular publication can still be one of your most valuable links.

Follow, nofollow, sponsored and ugc links

The rel attribute on a link tells Google what kind of link it is. Google's guide to qualifying outbound links lists three values, and its September 2019 announcement changed how they are used.

The key word is hint. Before 2019, Google did not count nofollow links as a ranking signal at all. In its September 10, 2019 post, Google said all three attributes "are treated as hints about which links to consider or exclude within Search." Google decides how to use each one alongside other signals.

What this means for you: chase followed editorial links, but do not dismiss nofollow links from trusted sites. And when you pay for a placement, including sending free products in exchange for a link, the link needs sponsored or nofollow. For a deeper look at followed links, read our guide to dofollow backlinks.

What makes a backlink high quality?

No tool can tell you exactly how Google values a link. Third-party scores such as Ahrefs' Domain Rating, Moz's Domain Authority and Majestic's Trust Flow are estimates built from each company's own crawl, and Google does not use them. They are still useful for comparing sites, as long as you compare like with like. Our guides to Domain Rating, Domain Authority and Trust Flow explain each one.

Beyond the scores, use this checklist to judge any link or link opportunity:

Anchor text deserves a closer look, since over-optimized anchors are one of the clearest signs of manipulation. Run your profile through our anchor text analyzer, and see our guide to anchor text SEO for what a natural mix looks like.

Backlinks Google treats as link spam

Google's spam policies define link spam as "the practice of creating links to or from a site primarily for the purpose of manipulating search rankings." The policy, last updated in August 2026, lists examples that include:

• Buying or selling links for ranking purposes, including exchanging money, goods or services for links, or sending someone a product in exchange for a post with a link.
• Excessive link exchanges ("link to me and I'll link to you") or partner pages built only for cross-linking.
• Using automated programs or services to create links to your site.
• Requiring a link as part of terms of service or a contract without letting the site owner qualify it.
• Advertorials or native ads where payment is received for articles with links that pass ranking credit, and links with optimized anchor text in guest posts or press releases distributed on other sites.
• Low-quality directory or bookmark site links, and links hidden in widgets distributed across many sites.
• Widely distributed links in the footers or templates of various sites, and forum comments with optimized links.

Google also says it actively fights this. In its December 14, 2022 link spam update, Google said it now uses SpamBrain, its AI-based spam prevention system, "to neutralize the impact of unnatural links on search results," and that SpamBrain can detect both sites buying links and sites used to pass outgoing links. In practice, a bought link is most often simply ignored, which means you paid for nothing.

Should you disavow spammy links pointing at you? Usually not. Google's disavow help page says that in most cases Google can assess which links to trust without additional guidance, and that the tool is an advanced feature that can harm your performance if used incorrectly. It is meant mainly for sites with a manual action for unnatural links that they cannot get removed.

How to earn external backlinks: 7 steps

The links that last are the ones a writer chose to give because your page helped their reader. For e-commerce brands, that means giving people something to cite beyond a product page. Our full guide to what link building is covers more tactics; this is the core process.

1. Benchmark your profile. Pull your referring domains and those of the three competitors that outrank you for your main category keywords. List sites that link to two or more competitors but not to you. Those are your warmest prospects.
2. Pick the pages you want to strengthen. Choose a few collection or product pages with real revenue potential, and the informational pages that can link to them.
3. Build one linkable asset. Original data from your own sales or customers, a sizing or compatibility guide, a care or how-to guide, or a useful calculator. Ask what a journalist or blogger in your niche would need to cite.
4. Reclaim what you have already earned. Find articles that mention your brand or products without linking and ask the writer to add a link. Our guide to unlinked brand mentions shows how.
5. Do targeted outreach and digital PR. Pitch your asset to specific writers who cover your topic, with a short note on why it helps their readers. Skip mass templates.
6. Use partner relationships honestly. Suppliers, stockists, brand ambassadors and charities you support often have a page that should mention you. Where money or product changes hands, ask for sponsored or nofollow.
7. Connect links to revenue pages. Once a link lands, add internal links from that page to your target collections and products, so the value reaches pages that sell.

How to audit and keep your backlinks

Earning links is half the job. Keeping them is the other half, because links decay. Ahrefs' link rot study (updated February 2024) looked at links to a sample of 2,062,173 websites since January 2013 and found that at least 66.5% had rotted. Counting other reasons, 74.5% of links had been lost for SEO purposes.

Nearly half of lost links disappeared because the linking page dropped out of the index, and about a third because the page still existed but the link had been removed. Your own site causes some losses too: if you delete or redirect pages that have links, those links are wasted or diluted.

A quarterly backlink check

• Find links to dead pages. Check which of your URLs that have backlinks now return 404 errors, and redirect each one to the closest live page. Our 404 redirect helper speeds this up, and the redirect checker confirms redirects resolve in one hop.
• Review lost links. If a valuable link was removed in a site redesign, a polite note to the site owner often gets it restored.
• Watch for sudden spikes. A burst of links from unrelated, low-quality sites is usually ignored by Google. Note it, but act only if you receive a manual action.
• Protect pages with links during migrations. Before replatforming to Shopify or changing URL structures, export your backlinked URLs and map every one to a redirect.

Turn backlinks into revenue

Start with a benchmark: your referring domains against the three competitors you most want to beat, and the list of sites that link to them but not you. Fix links pointing to dead pages, reclaim brand mentions, then build one asset worth citing and pitch it to the people who cover your category.

Measure the outcome in organic sessions and revenue on the pages you targeted, not in link counts. If you want help building that plan for your store, our e-commerce SEO team can benchmark your links against your competitors, or you can get in touch.