What is a Backlink? Definition & SEO Importance
Definition
A backlink (also called inbound link) is a hyperlink from another website pointing to a page on your site. Backlinks were the foundation of Google's original PageRank algorithm and remain one of the most influential ranking signals — high-quality, relevant backlinks are widely considered a top-three ranking factor.
What makes a backlink valuable
- Authority of the linking domain — links from established, trusted sites carry more weight.
- Topical relevance — a link from a related niche site means more than one from an unrelated domain.
- Anchor text — descriptive anchors help search engines understand the linked page.
- Editorial context — links surrounded by relevant content carry more weight than footer or sidebar links.
- Follow vs nofollow — followed links pass ranking signals more readily.
Protecting backlink value
- If a page that earns backlinks is deleted, set up a 301 redirect to a relevant alternative — never let a backlinked URL 404.
- Audit your inbound links periodically (Search Console, Ahrefs, Semrush) and reclaim broken ones.
- Scan your site regularly so backlinks never land on broken pages.
Earning quality backlinks is hard; losing their value through neglected redirects or broken pages is easy. Invest in both acquisition and maintenance.
Related terms
301 Redirect
The permanent redirect that preserves link equity and guides users.
Anchor Text
The visible, clickable text of a hyperlink that describes where the link leads.
nofollow
The link attribute that tells search engines not to pass ranking signals.
404 Error
What happens when a page can't be found — and how it affects SEO.
Internal Link
Links between pages on the same domain — the backbone of site structure.
www vs non-www
Choosing the canonical hostname — and why consistency matters more than the choice itself.