Glossary
Backlinks vs referring domains: what's the difference?
Backlinks count every individual link pointing to your site; referring domains count the unique websites those links come from. One site linking to you 500 times is 500 backlinks but one referring domain. Referring domains correlate better with rankings because they measure how many independent sites vouch for you.
Side by side
| Backlinks | Referring domains | |
|---|---|---|
| Counts | Each link | Each unique domain |
| Example: footer link on a 2,000-page site | 2,000 | 1 |
| Correlation with rankings | Weaker | Stronger |
| Quick to inflate | Yes | No |
Why the difference matters
A sitewide link or a forum signature can generate thousands of backlinks from one site. Ahrefs' large-scale studies find referring domain counts correlate with search traffic more than total backlinks do. Use referring domains to compare yourself with competitors and to measure link building.
Directories
Each directory listing typically adds one referring domain (and one or a few backlinks). Thirty listings on relevant directories is thirty referring domains, a meaningful start for a new site.
Example
A competitor shows 12,000 backlinks; the founder has 900. Comparing referring domains, it's 210 vs 180, much closer than it looked.
FAQ
Which should I track?
Referring domains, with backlinks for detail.
Does Google count referring domains?
Google doesn't publish its counting; independent sites linking is what its link signals reward.
Is one link per domain enough?
Additional links from the same site add less than a link from a new site.
Why did my backlinks jump but referring domains didn't?
Usually a sitewide link or many links from one site.