Backlinks vs Referring Domains in Link-Building

Last Updated on April 21, 2025

Link-building has long been one of the cornerstones of effective search engine optimization (SEO). Earning links from other websites not only increases your site’s visibility but also builds authority and trust in the eyes of search engines like Google. The more high-quality links pointing to your website, the better your chances of ranking higher in search results.

However, when exploring link-building strategies or using SEO tools like Ahrefs, SEMrush, or Moz, many people quickly stumble upon two commonly confused terms: backlinks and referring domains. While they’re closely related and often used interchangeably, they represent very different metrics, and misunderstanding them can lead to misguided SEO efforts.

In this blog, we’ll break down backlinks vs referring domains, explain why both matter for your SEO strategy, and share best practices to grow each one effectively. Whether you’re new to link-building or looking to fine-tune your plan, understanding this distinction will help you get more value from your SEO campaigns.

What is a Backlink?

A backlink is a hyperlink on one website that points to a page on another website. It’s essentially a vote of confidence from one site to another. Backlinks are also commonly referred to as inbound links or incoming links.

Example:
If a popular blog writes an article and includes a link to your website, that link is considered a backlink.

<a href=”https://yourwebsite.com”>Check out this helpful guide</a>

In this example, the hyperlink points to your website, which counts as a backlink.

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How Backlinks Work in SEO

Search engines like Google use backlinks as a significant ranking signal. The logic is simple: if multiple trustworthy websites link to a page, that page is likely to be authoritative and valuable.

Here’s what backlinks can do for your SEO:

• Increase your domain authority (DA) or domain rating (DR)
  
• Help search engines discover your content faster through crawling.
  
• Improve keyword rankings for the pages receiving links.
  
• Drive referral traffic from the linking website to yours.
  

However, not all backlinks are created equal. Links from high-authority, relevant websites carry more weight than those from spammy or unrelated sites.

Types of Backlinks (Dofollow, Nofollow, Sponsored, UGC)

Understanding the different types of backlinks helps you assess their value for SEO:

• Dofollow: Standard backlinks pass link equity (“link juice”). Search engines count them as ranking signals.
  
• Nofollow: These links contain a rel=”nofollow” attribute, signaling search engines not to pass link equity. While they don’t directly influence rankings, they can bring referral traffic and brand visibility.
  
• Sponsored: Used for paid links or advertising. These links include rel=”sponsored” to comply with Google’s link policies.
  
• UGC (User-Generated Content): Marked with rel=”UGC,” these links appear in content like blog comments or forum posts. Unless moderated carefully, they’re generally seen as lower-trust links.
  

What is a Referring Domain?

A referring domain is the domain (website) from which a backlink originates. In simpler terms, if multiple backlinks come from the same website, they are counted as coming from one referring domain.

Example:
If you get three backlinks from different blog posts on example.com, SEO tools like Ahrefs or SEMrush will count them as three backlinks from one referring domain.

This distinction is vital because having 100 backlinks from 100 different domains generally provides more SEO value than 100 backlinks from just one domain.

Difference Between Referring IPs and Referring Domains

While a referring domain tracks the domain name sending backlinks, a referring IP tracks the server’s IP address where the domain is hosted.

Why does this matter?

• Sometimes multiple domains are hosted on the same IP address (especially in shared hosting environments).
  
• If you have many backlinks from domains on the same IP or C-class IP, it may appear unnatural to search engines, as if those links were part of a link scheme.
  
• SEO tools use this data to help identify link diversity and detect patterns of manipulative link-building.
  

In short, referring IPs add an extra layer of analysis for evaluating the diversity and authenticity of your backlink profile.

Why Referring Domains Are Tracked in SEO Tools

SEO tools prioritize referring domains as a key metric because:

• Search engines trust link diversity — getting links from various domains signals broader authority and trustworthiness.
  
• It’s harder to manipulate the referring domain count than the total backlinks.
  
• High rankings often correlate more strongly with the number of unique referring domains than total backlinks.
  

That’s why platforms like Ahrefs, Moz, and SEMrush highlight referring domains front and center in their backlink analysis tools — it’s one of the most valuable indicators of your site’s backlink health and SEO potential.

Backlinks vs Referring Domains: Key Differences

Below is a comparison table outlining the key differences between Backlinks vs Referring Domains in SEO:

Comparison Point	Backlinks	Referring Domains
Definition	A hyperlink from an external website pointing to a page on your site (essentially a “vote of confidence” for your content). Often called inbound links.	The unique website (domain) from which a backlink comes. If multiple backlinks come from the same site, they all belong to one referring domain​.
Metric type	Link-level metric – counts every individual inbound link to your site​.	Domain-level metric – counts unique linking domains (each domain is counted once, no matter how many links it sends).​
How they are counted	Every link counts: Each external link is added to your total backlink count. For example, if one website links to you from 5 different pages, that’s 5 backlinks​.	Unique domains count: No matter how many links come from a single website, it counts as one referring domain. Using the same example, those 5 links from one site would be 1 referring domain.
SEO impact	Helps boost the SEO authority of the linked page (page-level ranking power)​. However, getting many links from the same site has diminishing returns and can appear spammy or manipulative to Google if overdone​.	Generally, it is a stronger SEO signal than raw backlink count. Google values having links from many different sites as a trust signal​, which boosts your site’s overall authority and trustworthiness (domain-level) and can improve rankings​.
Tool usage (Ahrefs, SEMrush, etc.)	It does not guarantee diversity by itself. You could have hundreds of backlinks from one or two sites, which means low diversity (e.g., 100 backlinks from one domain are far less valuable than 100 backlinks each from 100 different domains)​.	Emphasized as a key metric in SEO tools. Platforms like Ahrefs, SEMrush, and Moz put the referring domains count front and center, since it indicates link diversity and profile strength.
Link diversity	It does not guarantee diversity by itself. You could have hundreds of backlinks from one or two sites, which means low diversity (e.g., 100 backlinks from one domain are far less valuable than 100 backlinks each from 100 different domains)​.	Direct indicator of link diversity. A higher number of referring domains means your backlinks come from a wide range of different websites – something search engines prefer for natural link profiles.​
Quality considerations	Quality over quantity: Not all backlinks are equal. A single high-quality backlink from an authoritative, relevant site can outweigh dozens of backlinks from low-quality or spammy sites​.	Focus on acquiring links from reputable domains. A backlink from one trusted, relevant referring domain is far more valuable than many links from untrustworthy or unrelated domains​.
Typical use case	Used to gauge overall link-building progress and content popularity. For example, SEOs track total backlinks to see if a page is gaining links or if there’s a sudden spike (which could indicate viral content or potential spam)​. It’s a broad measure of how many total “votes” your site or page has accumulated.	Used to assess link diversity and the breadth of your site’s link profile. SEOs monitor referring domains to track how many unique sites endorse their content (gains or losses of referring domains signal outreach success or issues)​. In competitor analysis, looking at referring domains helps identify which websites are linking to competitors, revealing new outreach opportunities​.

Why Do People Think Referring Domains and Backlinks Are the Same?

Common Misconceptions

Surprisingly, it’s common — even among digital marketers — to confuse referring domains with backlinks. On the surface, they sound like they might be interchangeable, but they represent two very different metrics in link-building.

The confusion usually comes from being tied to external links pointing to your website. But here’s the catch:

• A backlink is a single link.
• A referring domain is the website from which the backlink came.

So if example.com links to your site from five different blog posts, that counts as:

• 5 backlinks
• 1 referring domain

Many assume backlinks always mean more SEO value, but search engines like Google prioritize link diversity. That’s why 10 backlinks from 10 domains are typically more valuable than 50 from just one.

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How Metrics from Tools Like Ahrefs and SEMrush Can Be Confusing

SEO tools can unintentionally blur the lines between backlinks and referring domains, especially for beginners. Here’s how:

• Tools often show both metrics side by side without clearly explaining the difference.
• Some dashboards highlight total backlinks as a large number, making them look more impressive than the unique referring domains.
• When tracking competitor link profiles, it’s easy to misjudge authority by focusing only on the backlink count rather than the source diversity.

For instance, you might see a competitor has 3,000 backlinks, but a deeper look reveals they’re coming from only 25 referring domains. That’s a red flag. It may mean they’ve received multiple sitewide or spammy links, which don’t carry the same SEO value as diverse, contextual ones.

The key takeaway? Don’t just chase big backlink numbers. Focus on acquiring links from a wide range of high-quality referring domains.

Backlinks vs Referring Domains: Key Differences Explained

Quantity vs Source Diversity

At first glance, it’s easy to think that more backlinks = better SEO. But that’s not always the case. The quantity of backlinks matters, but where they come from (source diversity) can make a much more significant impact.

• Backlink quantity refers to the total number of links pointing to your site.
• Source diversity refers to how many domains (referring domains) those links come from.

Example:

• Site A has 1,000 backlinks from 10 domains.
• Site B has 500 backlinks from 300 domains.

In most cases, Site B will have more substantial SEO potential. Search engines prefer natural link profiles, and getting links from a wide range of domains suggests your content is valuable to a broader audience.

Which One Matters More for SEO?

If you had to choose between the two, referring domains generally carry more weight in SEO than raw backlink count. Here’s why:

• Google values link diversity — it sees multiple domains linking to you as a stronger trust signal.
• Too many backlinks from the same domain can look spammy or manipulative.
• Many referring domains often correlate with higher rankings, especially in competitive niches.

That said, quality always trumps quantity. One backlink from a high-authority, relevant site (like Forbes or HubSpot) can be more potent than 100 from low-tier directories.

Impact on Authority and Trustworthiness

Search engines use backlinks and referring domains to assess a website’s authority, relevance, and trustworthiness. Here’s how:

• Backlinks help build page-level authority. If a specific page earns many links, it can rank higher for targeted keywords.
• Referring domains help build domain-level authority. If reputable sources consistently link to your site, it boosts your overall trust and rankings.

Think of it this way:
Backlinks are like individual votes.
Referring domains are like voters from different cities casting their votes.

When Google sees your content attracting links from a wide variety of trustworthy sources, it views your site as more credible and authoritative, which is precisely what you want for long-term SEO growth.

How Do Referring Domains Affect Organic Traffic?

Referral Traffic Potential

When you earn a backlink from a referring domain, you gain SEO value and open a potential referral traffic stream. Visitors who click the link from the referring site are funneled directly to your website.

This is especially valuable when the backlink comes from:

• A popular blog or news site
• A niche-relevant resource page
• A forum or community that your target audience uses

High-quality referring domains can drive consistent, high-intent traffic, even if the SEO impact is secondary.

Building Long-Term Traffic Sources

Unlike paid ads or social posts that lose momentum, backlinks from strong referring domains can continue to send traffic over time. A well-placed link in an evergreen blog post or industry guide can generate clicks for months or even years.

Here’s why that matters:

• It reduces your dependence on paid traffic.
• It builds brand awareness in your niche.
• It signals to Google that users find your content valuable.

This ongoing engagement can indirectly boost SEO, as search engines consider user behavior signals like time on site and bounce rate.

Relevance and Quality Over Quantity

Not all referring domains are created equal. A single backlink from a relevant, high-authority site (e.g., industry publications, .edu domains, trusted directories) can deliver more value in terms of SEO and referral traffic than dozens of links from low-quality, unrelated sites.

When evaluating referring domains, focus on:

• Topical relevance to your niche
• Domain authority or rating
• Organic traffic levels of the referring site
• Placement context (a link in a meaningful paragraph vs. footer or blogroll)

Remember: Google is smarter than ever about understanding link quality. If you want better rankings and real traffic, focus on earning links from sites that real people read and trust.

How to Check Backlinks and Referring Domains

Using Ahrefs, SEMrush, and Moz

You’ll need reliable SEO tools to understand your website’s link profile and how it compares to competitors. The top three in the industry are Ahrefs, SEMrush, and Moz, each offering robust backlink and referring domain analysis.

Here’s a quick overview of how each works:

• Ahrefs:
  • Navigate to Site Explorer
  • Enter your domain and hit search
  • Go to the Backlink Profile section → You’ll see metrics like Total Backlinks, Referring Domains, DR, and more
  • You can also view the Backlink Growth graph over time

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• SEMrush:
  • Use the Backlink Analytics tool
  • Enter your domain and click Overview
  • Scroll to see Referring Domains, Backlinks, Anchor Text, and Authority Score
• Moz:
  • Use the Link Explorer tool
  • Provides data on Inbound Links, Linking Domains, and Spam Score
  • Also highlights your Domain Authority (DA) and Page Authority (PA)

Each tool has strengths, but all clearly distinguish between total backlinks and unique referring domains—a crucial metric for tracking SEO health.

What to Look for in a Backlink Profile

When auditing your own or a competitor’s backlink profile, pay attention to:

• Number of Referring Domains vs. Total Backlinks
  → A balanced ratio is a good sign of natural link-building.
• Link Type Distribution
  → Dofollow vs. nofollow, UGC, sponsored — not all carry SEO value.
• Anchor Text Variety
  → Over-optimized anchor text (e.g., using the same keyword repeatedly) can trigger penalties.
• Link Placement
  → Contextual links (within content) are better than links in sidebars, footers, or comment sections.
• New vs. Lost Links
  → Tools like Ahrefs show when you gain or lose backlinks/referring domains, which is excellent for monitoring outreach success or spotting SEO issues.

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Analyzing Competitors’ Link Strategies

Want to reverse-engineer how competitors are ranking?

1. Plug a competing domain into Ahrefs or SEMrush
2. Go to the Referring Domains tab
3. Sort by domain authority or traffic
4. Identify the top-performing content that attracted those links
5. Replicate or improve it — then pitch to similar sources

This analysis helps uncover link-building opportunities you might’ve missed and shows what type of content earns the most backlinks in your niche.

Best Practices for Building Referring Domains and Backlinks

Getting backlinks is one thing, but earning them from high-quality, diverse referring domains is what moves the SEO needle. Here are some best practices to help you build a strong, natural link profile:

Create Great Content That Attracts Links Naturally

It all starts with content. To earn backlinks organically, your content needs to be:

• Useful – solve a real problem or answer a specific question
• Original – offer unique insights, stats, or research
• Linkable – format it with visuals, headers, and clear takeaways

Examples of link-worthy content include:

• Original surveys or case studies
• How-to guides or tutorials
• Industry reports and comparison posts
• Tools, templates, or calculators

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Guest Post on Relevant, High-Authority Sites

Guest posting is one of the most effective ways to build contextual backlinks and tap into new referring domains. Here’s how to do it right:

• Target niche-relevant websites, not just high-DA ones
• Personalize your pitch and suggest a valuable topic
• Include a natural link back to your site in the body or author bio
• Avoid sites that feel spammy or overly promotional

Bonus tip: Keep a spreadsheet of every site you’ve published to track domain diversity over time.

Manually Reach Out to Niche-Relevant Websites

Manual outreach still works when done with care and authenticity. Some popular tactics include:

• Broken link building: Find broken links on blogs and offer your content as a replacement
• Mention outreach: Reach out to sites that mentioned your brand without linking
• Skyscraper technique: Create something better than existing content, then pitch it to sites linking to the original

The key here is personalization. Nobody responds to mass, generic emails anymore.

Avoid Spammy Link-Building Tactics

Not all backlinks are good backlinks. Avoid strategies that could harm your SEO in the long run, such as:

• Buying links from shady sources
• Using automated link-building software
• Relying on private blog networks (PBNs)
• Over-optimizing anchor text

Google is smarter than ever, and low-quality links can lead to manual actions or algorithmic downgrades.

Diversify Your Link Sources for Better Impact

If 80% of your backlinks come from just a few domains, that’s a red flag.

Aim for a broad mix of domains, including:

• Blogs
• News outlets
• Industry directories
• Forums and communities
• Educational or government sites (when relevant)

A healthy link profile should look natural and diverse, not manipulated or overly concentrated.

How to Get More Referring Domains to Increase SEO Ranking

Earning backlinks is essential, but earning them from new referring domains is where the real SEO growth happens. Here are proven strategies to help you expand your referring domain count effectively:

Leverage Digital PR and News Mentions

One of the fastest ways to earn links from authoritative domains is through digital PR. If you have something newsworthy — a product launch, industry insight, or original data — get it in front of journalists and bloggers.

Tactics to try:

• Publish press releases for big announcements
• Build relationships with industry journalists and editors

When your story gets picked up, it often results in links from significant publications — high-authority, high-traffic referring domains.

Try our authority score calculator.

Publish Original Research and Statistics

People love linking to data-driven content, especially bloggers, journalists, and content marketers who want to support their claims.

Here’s what works:

• Run a small survey in your niche and share the results
• Compile industry benchmarks or trends
• Analyze publicly available data and turn it into insights

Make your research visually appealing with charts, graphs, and infographics, which increases its linkability even more.

Offer Linkable Assets Like Tools, Templates, and Checklists

Creating evergreen, utility-based content is a great way to attract links naturally over time. Some ideas:

• Free SEO audit tools
• Website calculators
• Marketing strategy templates
• Printable checklists or PDF downloads

The more useful and easy-to-share your content is, the more likely it is to get picked up and linked to by other sites.

Build Resource Pages and Ultimate Guides

Resource pages are link magnets — especially if they’re comprehensive and well-organized. These include:

• “Ultimate guides” on niche-specific topics
• Curated lists of tools, strategies, or case studies
• Beginner’s tutorials that others can reference

Promote these pages through targeted email outreach, social media, and relevant online communities to increase visibility.

Conduct Expert Roundups and Collaborative Content

Invite industry experts or influencers to contribute a quote, insight, or tip to your content. Once it’s live, most of them will naturally link to it, giving you backlinks from new referring domains.

Bonus: You build relationships and grow your network simultaneously.

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