Domain Authority Explained: What It Is and Why It Matters

Domain Authority is one of the most referenced—and most misunderstood—metrics in SEO. Here's what you actually need to know.

What Is Domain Authority?

Domain Authority (DA) is a metric developed by Moz that predicts how likely a website is to rank in search results. It's scored on a scale of 1-100.

Key points:

• DA is a Moz metric, not a Google metric
• Google does not use DA in their algorithm
• It's a comparative tool, not an absolute measure

How It's Calculated

Moz calculates DA using machine learning models that consider:

• Total number of backlinks
• Quality and diversity of linking domains
• Other proprietary factors

They compare these signals to sites that rank well and assign scores accordingly.

What DA Is Good For

DA is useful as a quick comparative metric:

Prioritizing outreach targets A DA 50 site is generally more valuable than a DA 20 site, all else equal.

Competitive benchmarking Compare your DA to competitors to understand relative strength.

Quick quality screening Filter out obviously low-quality sites without deep analysis.

What DA Is Not Good For

Don't overvalue DA:

It's not a Google ranking factor Google doesn't see or use DA. High DA doesn't guarantee rankings.

It doesn't account for relevance A DA 30 site in your niche may outperform a DA 70 site in an unrelated space.

It fluctuates DA changes when Moz updates their index. A 5-point drop might mean nothing.

It can be manipulated Sites can artificially inflate DA through PBNs or link schemes.

DA vs. DR

Ahrefs has their own metric: Domain Rating (DR).

Key differences:

• Different calculation methods
• Different scales in practice
• Neither is "better"—they measure similar but distinct things

Use whichever tool you have access to, but don't mix comparisons.

Using DA in Link Building

Here's how to use DA appropriately:

Do:

• Use as one factor among many
• Compare sites within the same niche
• Set DA thresholds for prospecting (e.g., DA 30+)

Don't:

• Reject relevant sites just because DA is "low"
• Chase high-DA sites in irrelevant niches
• Pay extra just for higher DA

A Better Framework

Instead of focusing solely on DA, evaluate link opportunities on:

1. Relevance - Is the site topically relevant?
2. Authority - Does it have real traffic and engagement?
3. Quality - Is the content genuinely good?
4. Link context - Where will your link appear?

DA is one input to the "authority" consideration, not the only one.

DA Score Guidelines

General guidelines (these vary by industry):

• DA 1-20: New or small sites. May be valuable if highly relevant.
• DA 21-40: Established sites with some authority. Good targets for most link builders.
• DA 41-60: Strong sites. Often worth extra effort to earn links.
• DA 61-80: High authority. Major publications and established brands.
• DA 81-100: Top sites globally (major news sites, Wikipedia, etc.)

Remember: a DA 35 site in your niche often delivers more value than a DA 65 site that's off-topic.

Checking Domain Authority

Free ways to check DA:

• Moz Link Explorer (limited free queries)
• MozBar Chrome extension
• SEO toolbars that include DA

For bulk checking, you'll need a paid tool subscription.

Common Questions

"What's a good DA?" Depends on your space. Compare to competitors and target sites above your current DA.

"How do I increase my DA?" Build quality backlinks. DA follows good SEO practices.

"My DA dropped suddenly. What happened?" Moz updated their index. Check if your backlink profile actually changed.

"Is DA the same as Page Authority (PA)?" No. DA is for the whole domain. PA is for individual pages.

Authority Signals and AI Search

The same signals that build domain authority—quality backlinks, citations from trusted sites, and a diverse linking profile—also influence whether AI assistants surface your brand. Tools like ChatGPT, Perplexity, and Gemini lean on the same web of authority and references when deciding which sources to trust and cite in their answers.

You won't find a DA score inside these models, but the underlying pattern carries over: brands that earn credible mentions and links tend to show up more often, and more confidently, in AI-generated responses. If you're already building authority for search rankings, you're laying groundwork for AI visibility too.

For a closer look at how this connection works, see do backlinks help AI search.

The Bottom Line

Domain Authority is a useful shorthand for site quality, but it's not the ultimate measure of a link's value.

Use DA as a screening tool and for quick comparisons. But always look deeper at relevance, traffic, content quality, and actual audience before deciding if a link opportunity is worthwhile.