Backlinks
A backlink is a link from another website to yours. Search engines treat backlinks as votes of confidence: when a trusted, relevant site links to your page, it suggests your content is worth recommending. Backlinks have been one of Google’s most important ranking signals since its earliest days (PageRank).
Why backlinks matter
- Rankings: pages with more high-quality backlinks tend to rank higher, especially for competitive keywords.
- Discovery: search engines find new pages by following links from other sites (Crawling).
- Referral traffic: links on relevant sites send interested visitors directly.
- Authority and trust: links from respected sources support E-E-A-T.
- AI visibility: widely cited sources are more likely to be referenced in AI answers.
What makes a good backlink
- Relevance: the linking site and page are about a related topic.
- Authority: the linking site is trusted and well linked itself.
- Editorial placement: the link was given freely within content, not bought or forced.
- Context: surrounded by relevant text, ideally in the main body of the page.
- Traffic: the linking page has real readers who might click.
- Descriptive Anchor Text that reflects your page’s topic, without being over-optimised.
- Followed: a normal link without nofollow or sponsored attributes passes the most value (Nofollow, Sponsored and UGC Links).
One link from a respected industry publication can be worth more than hundreds of links from low-quality directories.
What makes a bad backlink
- Links from spammy, hacked or irrelevant sites.
- Paid links that pass ranking value without being marked as sponsored.
- Links from private blog networks or link farms.
- Sitewide footer or sidebar links on unrelated sites.
- Large numbers of exact-match keyword anchors.
These can be ignored by Google or, in serious cases, lead to manual actions. See Toxic Backlinks.
Quantity vs quality
The number of different websites linking to you, Referring Domains, matters more than the total number of links. Ten links from ten relevant sites are generally more valuable than a hundred links from one site.
How to check your backlinks
- Google Search Console: the Links report shows top linking sites and pages.
- SEO tools: Ahrefs, Semrush, Majestic and others show larger link indexes, anchor text and new and lost links (SEO Tools).
- Compare with competitors: identify sites linking to them but not to you.
How to earn backlinks
Create genuinely useful content, share original data, contribute expert commentary through Digital PR, build relationships in your industry and fix broken or unlinked mentions. The full approach is covered in Link Building.
How backlinks pass value
Links pass Link Equity from one page to another. Pages that receive many links can pass some of that value to other pages through internal links, which is why a strong Internal Linking strategy multiplies the benefit of every backlink you earn.
Key Takeaways
- A backlink is a link from another website to yours.
- Relevant, editorial links from trusted sites are the most valuable.
- The number of referring domains matters more than total link count.
- Bought and manipulative links risk penalties.
- Internal links spread the value of backlinks to other pages.
Related Terms
Want to know where your site stands? Book a free SEO health check, or keep learning in the SEO Encyclopedia.