Inbound Link
An inbound link is a link that points from another website to a page on your site. Search engines read these links as signals of a page's credibility and authority, which is why they are also called backlinks or incoming links.
- An inbound link is a link from another website to your own, and the terms backlink, incoming link, and inlink all describe the same thing.
- It runs in the opposite direction from an outbound link, which leaves your site, and from an internal link, which connects pages within the same domain.
- Google treats inbound links as a vote of confidence from other sites, and any link without a nofollow attribute passes PageRank, or link equity, to the target page.
- Quality matters far more than quantity: one link from an authoritative, topically relevant site can outweigh thousands of low-quality ones.
- Ahrefs' Domain Rating, Semrush's Authority Score, and Moz's metrics all lean on a site's inbound link profile as a core input.
Definition
An inbound link is a hyperlink on another website's page that points to your own site. Ahrefs defines it as "a link from one website to another" and notes that the same thing goes by several names: backlink, incoming link, and inlink. In other words, "inbound link" and "backlink" are simply different labels for the same concept.
The key idea is direction. When an external site links to one of your pages, that link is inbound from your perspective. At the same time, for the site that placed it, the very same link is an outbound link leaving their site. A single link is therefore classified as inbound or outbound depending on whose vantage point you take.
Backlinks, Outbound Links, and Internal Links
The three link types are distinguished by direction and by domain. Because an inbound link and a backlink are the same concept, the table below lists "backlink" as another name for the inbound link.
| Type | Direction | Domain | SEO role |
|---|---|---|---|
| Inbound link (= backlink) | External → your site (incoming) | Originates on another domain | Receives authority and trust signals; brings in PageRank |
| Outbound link | Your site → external (leaving) | Points to another domain | Passes some authority outward; supports content credibility |
| Internal link | Your site → your site | Within the same domain | Connects site structure; distributes received link equity internally |
To sum up, inbound and outbound links are alike in that both cross domain boundaries, but their direction is exactly reversed. Inbound links bring authority into your site, while outbound links send a share of your authority elsewhere. Internal links stay within a single domain and spread the authority you have earned across your other pages.
Why Inbound Links Matter for SEO
Inbound links matter because search engines interpret them as a vote of confidence. According to Ahrefs, when authoritative, topically relevant sites link to a page, Google reads that as a signal that the page's information is high quality and trustworthy. This principle traces back to the PageRank algorithm of more than two decades ago, and any link without a nofollow attribute passes PageRank, or link equity, to the page it points to.
More is not automatically better, however. Google prioritizes quality over quantity, and a single strong link from an authoritative, on-topic site can carry more weight than thousands of low-quality ones. The factors that shape a link's value include the authority of the source page, topical relevance, natural anchor text, whether it is dofollow, and placement near the top of the body content.
Dofollow and Nofollow
Inbound links fall into dofollow and nofollow varieties depending on their attributes. A dofollow link, which carries no special attribute, is treated as a standard endorsement that search engines follow and pass authority through. When a publisher adds an attribute such as rel="nofollow", rel="sponsored", or rel="ugc", it signals that the link is not an endorsement, or that it is a paid or user-generated link.
<!-- dofollow: passes authority (default) -->
<a href="https://example.com/article">Related resource</a>
<!-- nofollow: not an endorsement -->
<a href="https://example.com/ad" rel="nofollow">Ad link</a>Measurement Metrics
The major SEO tools rely on a site's inbound link profile as a core basis for measuring authority.
- Ahrefs Domain Rating (DR): A metric for a site's overall authority, based on the quantity and value of the inbound links it has earned.
- Semrush Authority Score (AS): A 0–100 measure of a domain's SEO strength, combining link power (the quality and quantity of backlinks), organic traffic, and how natural the link profile is.
- Moz: Evaluates backlink strength by weighing domain authority, anchor text, page relevance, and similar factors.
- Google Search Console: Lets you review the links pointing to your site for free.
Action Checklist
- Earn inbound links from authoritative, topically relevant sites, prioritizing quality over sheer count.
- Keep anchor text natural rather than over-optimizing it with target keywords.
- Regularly check whether links are dofollow and how trustworthy their source sites are.
- Monitor your inbound link profile with Search Console, Ahrefs, Semrush, and Moz, and manage any spammy links.
- Tidy up your internal link structure so the inbound authority you receive flows across the whole site.