Domain Authority vs Domain Rating: What's the Difference?

If you've spent time in SEO, you've seen both metrics: Moz's Domain Authority (DA) and Ahrefs' Domain Rating (DR). Both score websites on a 0–100 scale, both claim to measure "authority," and both are widely used in link-building and competitor analysis. But they're built by different companies using different algorithms — and understanding domain authority vs domain rating matters when you're deciding which number to trust.

This guide breaks down how each metric works, where they diverge, and which one you should track.

What Is Domain Authority (DA)?

Domain Authority is Moz's proprietary metric, introduced in 2004 and updated several times since. It predicts how likely a domain is to rank in search engine results. DA uses a machine learning model trained against Google's actual rankings, incorporating dozens of link-related factors:

• Number of linking root domains
• Quality and relevance of linking sites
• Moz's own MozRank and MozTrust scores
• Spam scores of linking domains

DA is a predictive metric — it's designed to correlate with ranking ability, not to measure raw link strength. Moz recalibrates the scale periodically, which means DA scores can shift even if your backlink profile hasn't changed. That's by design, not a bug.

What Is Domain Rating (DR)?

Domain Rating is Ahrefs' metric, launched later than DA. It measures the strength of a domain's backlink profile in absolute terms — specifically, the quantity and quality of referring domains pointing to the entire domain.

DR's algorithm focuses on:

• Number of unique referring domains
• The DR of those referring domains (recursive weighting)
• How many outbound links each referring page has

Unlike DA, DR is not trained against Google rankings. It's a pure backlink-strength score. This makes it more stable — your DR only changes when your backlink profile changes — but it doesn't directly predict rankings the way DA attempts to.

DA vs DR: Side-by-Side Comparison

Key Differences

What They Measure

DA predicts ranking ability. DR measures backlink strength. A site with a strong link profile but poor on-page SEO might have a high DR but rank poorly — DA would reflect that gap better because it's trained on actual rankings.

Data Sources

Moz and Ahrefs maintain separate crawlers and link indexes. They don't see the same backlinks. Ahrefs' index is generally larger for backlink discovery, while Moz's index includes spam analysis and trust metrics. This means the same site will almost always have different DA and DR scores — sometimes by 10+ points.

Stability

DR only changes when your backlink profile changes. DA can shift during Moz's recalibrations even if your links haven't moved. For tracking link-building progress month over month, DR is more reliable. For a snapshot of ranking potential, DA may be more informative.

Scale Interpretation

Both are logarithmic, but the curves differ. A DR of 50 means you have more referring domains than roughly 5% of all sites in Ahrefs' index. A DA of 50 doesn't map to the same percentile in Moz's index. Don't compare DA and DR directly — compare DA to DA and DR to DR.

Which Should You Track?

Track both if you can. Each tells you something the other doesn't:

• Use DR to measure your link-building progress. It's stable, directly tied to backlinks, and easy to track over time.
• Use DA to gauge competitive positioning. Since it's trained on rankings, it's a better proxy for "can this site rank?"
• Use both when evaluating link partners. A site with DA 55 but DR 20 might have spammy links that inflate DA but don't pass real authority.

For free checks, use our domain rating checker to get DR quickly. For DA, Moz's Link Explorer offers a few free queries per month.

Practical Use Cases

Competitor Analysis

Compare your DR to competitors' DR to gauge the link gap. Then compare DA to see if their ranking advantage is link-driven or content-driven. A competitor with similar DR but higher DA may be winning on on-page factors, not links.

Link Outreach

Filter prospects by DR first (fast, stable), then check DA for the shortlist. Skip sites where both metrics are low — they won't pass meaningful authority.

Site Acquisition

Check both metrics before buying a domain. A high DA with low DR can indicate a site that ranked well historically but has a weak current link profile. Cross-reference with an SSL checker and IP lookup to verify the site's infrastructure matches its claimed authority.

Summary

Domain Authority and Domain Rating both score website authority on a 0–100 scale, but they use different data, different algorithms, and different philosophies. DA predicts rankings; DR measures backlink strength. Neither is "better" — they answer different questions. Track DR for link-building progress, DA for ranking potential, and always compare like-to-like. For a fast, free DR check, use the online checker and pair it with other signals before making decisions.