Almost every guide on this topic stops at the definition. Backlinks are total links, referring domains are unique sites, here's a diagram, goodbye.
That's not useful. You already have both numbers sitting in Ahrefs. What you actually need to know is which number to act on this month, and what your ratio between them is telling you about the campaign you're running.
This guide answers that. It's written from what we see across 30,000+ placements built for 500+ companies, and it's structured as a diagnostic: read your own profile, work out which of four situations you're in, and know what to do next.
Quick Answer
Backlinks are the total number of links pointing to your website. Referring domains are the number of unique websites those links come from. Referring domains drive domain-level authority; backlinks concentrate authority on specific pages. If you are choosing where to spend next month, choose referring domains.
Total links pointing to your site. Build depth on one page.
Unique websites linking to you. Build authority across the domain.
The 60-second version
One site linking to you from twenty articles is twenty backlinks and one referring domain. Twenty different sites linking once each is twenty backlinks and twenty referring domains. Same headline number, completely different signal.
The second profile is harder to manufacture, which is exactly why it carries more weight. Getting one publisher to link to you repeatedly takes one relationship. Getting twenty independent publishers to do it takes twenty separate decisions that your content was worth citing.
Which Looks More Trustworthy?
100 Backlinks
From 1 website
1 Referring Domain
100 Backlinks
From 100 websites
100 Referring Domains
Diagnose your own profile in five minutes
Open Ahrefs Site Explorer (the free Webmaster Tools version works for your own domain) and write down four numbers:
- Total backlinks and total referring domains from the Overview.
- Your backlinks-to-domains ratio: divide the first by the second.
- Referring domains gained in the last 90 days, from the Referring Domains chart.
- Referring domains pointing at your money pages, from Best by Links, filtered to the URLs that generate revenue.
That fourth number is the one almost nobody checks, and it's usually where the problem is. Plenty of sites have a healthy domain-level profile and commercially useless pages, because every link they ever earned went to the homepage or the blog.
What your ratio is actually telling you
There is no correct ratio, and anyone quoting one is selling something. But the ratio is diagnostic: it tells you which kind of campaign produced your current profile.
| What you see | What it usually means | What to do next |
|---|---|---|
| Low ratio (close to 1 link per domain) | A young or outreach-led profile. Each site linked once. Healthy, but shallow on any single page. | Keep adding new domains, then add depth to your two or three most commercial pages. |
| High ratio (many links, few domains) | Sitewide links: footers, sidebars, blogrolls, widgets. Often one partner or template linking from every page. | Check where the volume comes from. Sitewide links add little beyond the first one, so treat the domain count as your real number. |
| Domains rising, rankings flat | Links are landing on the wrong URLs, or on sites with no topical relationship to yours. | Re-point the next ten placements at the pages you actually want to rank. |
| Ratio spiking suddenly | A scraped or syndicated page, or a low-quality network replicating one link across a domain. | Audit the source before doing anything else. See our guide to spotting a link farm. |
Which one should you build this month?
Use the situation you're actually in, not the general rule.
You're under roughly DR 20
Build referring domains. At low authority the problem isn't page-level competitiveness, it's that Google has too little evidence your domain is a real business. Breadth solves that faster than depth. In one campaign on a brand-new SaaS domain, foundational listings and editorial placements took the site to DR 19 within two months, and that lifted every page, not one.
You have a specific page stuck on page two
Build backlinks to that URL. This is the case where more links from sites already linking to you genuinely helps, because you're concentrating authority on one target rather than spreading it. Link insertions on relevant, already-ranking articles do this faster than fresh guest posts, since the host page already has age and traffic.
Your domain metrics look fine but nothing converts
Rebalance, don't build. Check the split of referring domains across your homepage, comparison pages, feature pages and blog. If 80% point at the homepage, your next ten placements should point at commercial pages instead. This is the single most common problem we see in SaaS profiles.
You're being outranked by a site with fewer links
Look at relevance, not volume. A mid-authority site squarely in your niche routinely outperforms a large, unrelated one. Run a competitor backlink analysis and compare the topical overlap of their referring domains against yours, not just the counts.
What the counts don't show you
Three things matter more than either headline number, and neither metric captures them.
Whether the linking page gets traffic. A DR 55 domain with 200 monthly organic visitors is worth less than a DR 42 domain with 15,000. Domain Rating reflects backlink volume, not readership. The clean way to think about that difference is in our breakdown of domain rating vs domain authority.
Which page the link points at. Ten referring domains pointing at a blog post about industry trends do very little for a comparison page trying to rank. Authority is page-specific before it is domain-wide.
Whether the link sits in real content. A link inside an article body, surrounded by related text, behaves differently from one in a sidebar, footer or author bio. The counts treat them identically. Google does not.
Referring Domains
Show how widely your authority is recognized. Build these first.
Backlinks
Concentrate authority on a specific page. Build these when one URL needs a push.
How to add referring domains that count
Four approaches, in the order they tend to work for a site under DR 30.
Claim what you've already earned. Unlinked brand mentions, partner and integration directories, investor or accelerator pages, podcast show notes. These convert at a far higher rate than cold outreach because the relationship already exists, and most companies never ask.
Publish something only you can publish. Aggregate your own product or campaign data into a benchmark nobody else can produce. Journalists and bloggers need numbers to cite, and a benchmark page earns domains for years rather than weeks.
Founder-led contributions. Editors will publish operational detail from someone who has actually done the thing, when they would reject the same topic from a content team. Your unfair advantage is specificity.
Fill the gaps your competitors already proved. Sites linking to three competitors but not to you have already demonstrated they'll link to companies like yours. Our backlink gap analysis guide covers how to turn that export into a target list, and the link building tools guide covers what to run it with.
Managing what you've already got
Don't panic over weak links. Google filters most low-quality backlinks on its own. Proactive removal matters if you have a manual action or a history of bought links; otherwise, monitor rather than react.
Watch the shape of growth, not just the count. Domains appearing steadily looks like a business earning attention. A flat line followed by a spike looks like a purchase.
Vary anchor text. A profile dominated by exact-match commercial anchors is one of the easier patterns to detect. Branded and generic anchors should make up most of it.
Frequently Asked Questions
What is a referring domain?
A referring domain is a unique website that points at least one backlink to your site. However many links that site sends, it counts once.
Are backlinks and referring domains the same thing?
No. Backlinks count links; referring domains count the websites those links come from. One site linking ten times is ten backlinks and one referring domain. The headline number looks the same, the signal is not.
Are referring domains more important than backlinks?
For domain-level authority, yes, and that's where most sites should start. Backlinks matter when a specific page needs to move: concentrating links on one URL does something breadth cannot.
What's a good backlinks-to-referring-domains ratio?
There isn't a target worth chasing. The ratio is useful as a diagnostic, not a goal: a very high ratio usually means sitewide links from few sources, and a low one usually means an outreach-led profile with little page-level depth.
How many referring domains do I need to rank?
It depends entirely on the keyword. The practical answer is to count the referring domains pointing at the specific pages ranking in the top five for your target term, not at their domains overall, and treat that as the bar to clear.
Do multiple links from the same site still help?
Yes, but with diminishing returns, and they help a page rather than the domain. The exception worth knowing is sitewide links from footers or sidebars, where the second link onwards adds very little.
How fast should referring domains grow?
Steadily. A consistent handful of new domains each month looks like a business earning coverage; a sudden spike after months of nothing looks like a transaction, and is treated accordingly.
The bottom line
Referring domains tell Google how widely you're recognized. Backlinks decide which of your pages that recognition lands on. The useful question is never "which metric matters more", it's "which of these is currently the constraint on the page I need to rank?"
Answer that with the five-minute diagnostic above, and you'll know where the next ten links should go.
If you'd rather not run that campaign yourself, our SaaS link building service maps every placement to the page it's meant to move, with each site pre-approved by you and pay-per-placed-link pricing. Book a call and we'll show you the gap between your referring domains and your three closest competitors.
