When reviewing backlink data, you'll encounter two related but distinct metrics: Total Backlinks and Referring Domains. Understanding the difference—and why referring domains often matter more—helps you evaluate link profiles more accurately.
Defining the Metrics
Total Backlinks counts every individual link pointing to a domain. If a single website links to you from ten different pages, that contributes ten backlinks to your total.
Referring Domains counts the number of unique websites linking to you. Using the same example, those ten links from one website count as just one referring domain.
Why Referring Domains Deserve More Attention
Search engines value link diversity. A vote of confidence from many different sources carries more weight than repeated votes from the same source.
Consider two scenarios:
Scenario A: A website has 500 total backlinks from 300 different referring domains. Each link represents a unique website vouching for the content.
Scenario B: A website has 500 total backlinks from just 10 referring domains. The same few sites link repeatedly, but the broader web hasn't endorsed the content.
Scenario A reflects a more robust, trustworthy profile. The links come from diverse sources, suggesting genuine interest across the web. Scenario B concentrates authority in a handful of sources—a pattern that could look artificial and creates risk if any of those sources disappear or lose credibility.
Tip: When setting link-building goals, prioritize acquiring links from new referring domains rather than stacking additional links from sites that already link to you.
How Concentration Risk Affects Your Profile
If a significant portion of your backlinks come from one or two domains, you face concentration risk. Should those domains:
Remove their links to you
Get penalized by search engines
Go offline entirely
...you could lose a substantial chunk of your link equity overnight. Diversification protects against this vulnerability.
Review your Referring Domains list periodically. If one domain contributes more than 10–15% of your total backlinks, consider whether that concentration is strategic (e.g., a major media feature) or incidental.
Evaluating Competitors Using This Lens
When comparing your backlink profile to competitors, look at the ratio of backlinks to referring domains.
Domain | Total Backlinks | Referring Domains | Ratio |
|---|---|---|---|
Your site | 800 | 450 | 1.8:1 |
Competitor A | 2,000 | 400 | 5:1 |
Competitor B | 600 | 500 | 1.2:1 |
In this example, Competitor A has more total backlinks but fewer referring domains, resulting in a high ratio. This could indicate link concentration or repeated sitewide links. Competitor B has fewer total backlinks but more referring domains—a potentially healthier, more diverse profile.
Use these insights to contextualize raw numbers and identify realistic benchmarks for your own growth.