What Is a Backlink? Definition and Examples
A link from an external website to your page, and one of the most important ranking factors in SEO.
What is a backlink?
A backlink is an incoming link from an external website to your page. Since Google's early days, backlinks have been one of the most important ranking factors, because search engines read them as a recommendation.
Example: a Swiss trade magazine publishes an article about energy-efficient buildings and links to a planning firm's guide on heat pumps. For the planning firm, that link is a backlink from a relevant, trusted source.
Why do backlinks matter?
Google treats backlinks as a trust signal. The more high-quality websites link to your content, the higher Google rates the authority of your domain. What counts:
- Quality over quantity – one link from a respected source is worth more than a hundred links from unknown sites
- Topical relevance – links from sites on related topics carry more weight
- Natural link profile – Google detects unnatural link patterns and can penalize them
A backlink is the result. Link building is the work of earning such links on purpose. If links were bought for your website in the past, our guide on checking and cleaning up your link profile explains what to do.
Backlinks and AI visibility
Backlinks also play a role in LLMO and GEO: AI models such as ChatGPT prefer sources with high authority. A strong backlink profile signals trustworthiness, both to Google and to AI systems.
Frequently asked questions
What is a backlink?
A backlink is a link from an external website to your page. Search engines read it as a recommendation and use it as one of their most important ranking factors.
Why do backlinks matter for SEO?
Google treats backlinks as a trust signal. Links from respected sites on related topics raise the authority of your domain, while unnatural link patterns can lead to penalties.
What is an example of a backlink?
A Swiss trade magazine writes about energy-efficient buildings and links to a planning firm's guide on heat pumps. For the planning firm, that link is a backlink.
How does a backlink differ from link building?
A backlink is a single link pointing to your site. Link building is the ongoing work of earning such links from relevant, trusted websites.