What Is URL Rating (UR) and How Is It Different from Page Authority (PA)?
Both URL Rating and Page Authority measure the strength of individual web pages. Both are used by SEO professionals to evaluate how well a specific page might rank. Both are based on backlinks.
So why do they often show completely different numbers for the same page?
Because they come from two different companies, use two different methodologies, and are measuring slightly different things — even if the goal looks the same on the surface.
This guide explains exactly what URL Rating is, what Page Authority is, how they differ, which one to trust, and when to use each one in your SEO work.
What Is URL Rating (UR)?
URL Rating (UR) is a metric developed by Ahrefs that measures the strength of a specific page’s backlink profile. It scores pages on a scale from 0 to 100 using a logarithmic scale.
The name tells you exactly what it does: it rates individual URLs. Not domains — specific pages. A blog post, a landing page, a product page — each has its own UR based entirely on the backlinks pointing directly to that URL.
UR is one of two core metrics Ahrefs uses to evaluate authority:
- URL Rating (UR) — measures individual page strength
- Domain Rating (DR) — measures overall website strength
Think of UR as Ahrefs’ answer to the question: “How powerful is this specific page based on who links to it?”
Key facts about URL Rating:
- Created by Ahrefs
- Scale: 0 to 100 (logarithmic)
- Measures: Backlink strength of a single URL
- Updates: Near real-time as Ahrefs crawls new links
- Considers: Both internal and external links pointing to the page
What Is Page Authority (PA)?
Page Authority (PA) is a metric developed by Moz that predicts how well a specific page is likely to rank in search engine results. It also scores pages from 1 to 100 on a logarithmic scale.
PA goes one step beyond raw link counting — it uses a machine learning model to translate link signals into a ranking prediction. Moz trained this model on real Google search data, so PA is designed to correlate with actual search performance rather than just measuring link volume.
Key facts about Page Authority:
- Created by Moz
- Scale: 1 to 100 (logarithmic)
- Measures: Predicted ranking potential of a single page
- Updates: Monthly (with Moz’s index refresh)
- Considers: External backlinks, internal links, and quality signals, including spam detection
UR vs PA — Direct Comparison
| URL Rating (UR) | Page Authority (PA) | |
|---|---|---|
| Created by | Ahrefs | Moz |
| Scale | 0 to 100 | 1 to 100 |
| What it measures | Backlink strength of the page | Predicted ranking likelihood of the page |
| Includes internal links | Yes — weighted separately | Yes |
| Spam detection | No | Yes — through Moz’s Spam Score system |
| Update frequency | Near real-time | Monthly |
| Paired domain metric | Domain Rating (DR) | Domain Authority (DA) |
| Best used for | Link building, backlink analysis | Ranking potential, competitive analysis |
How URL Rating Is Calculated
Ahrefs calculates UR using a methodology very similar to Google’s original PageRank algorithm — but applied only to the pages in Ahrefs’ crawl index.
Here is how the logic works:
Every page starts with a base value. That value gets distributed among pages it links to — both internal pages on the same site and external pages on other sites. The more links a page gives out, the smaller each individual share.
Internal links count — but differently. Ahrefs separates internal link equity from external link equity in its UR calculation. A page receiving many internal links from high-UR pages on the same site will see its UR rise, but the effect is weighted less heavily than external backlinks from other domains.
The quality of linking pages matters more than quantity. A single link from a page with UR 80 contributes significantly more to your UR than 50 links from pages with UR 10. The algorithm is iterative — every page’s UR depends on the UR of pages linking to it, which in turn depends on pages linking to them.
Logarithmic scaling means big gaps between high scores. Moving from UR 30 to UR 40 requires far more link authority than moving from UR 10 to UR 20. Pages with UR above 70 are typically the most linked-to pages on major publications — news articles that went viral, Wikipedia entries, government resource pages.
How Page Authority Is Calculated Differently
While UR is essentially a link flow calculation, PA is a machine learning prediction model.
Moz did not just count links and call it PA. They trained a model to answer: “Given what we know about the links pointing to this page, how well is it likely to rank in Google?”
The inputs to PA include:
External backlinks to the page — how many links from other websites point to this specific URL, and how authoritative those linking pages are
Internal links from other pages on the same site — each internal link transfers a portion of the linking page’s own Page Authority
MozRank of the page — Moz’s link popularity score, which feeds into PA as a core input
Quality and spam signals — pages that attract links from spammy, penalized, or low-quality sources get penalized in PA. Moz’s spam detection is baked into the PA calculation in a way that Ahrefs’ UR is not
Link diversity — the variety of domains, anchor texts, and link types pointing to the page
Because PA uses machine learning trained on real search ranking data, it is designed to correlate with actual Google positions — not just link power in the abstract.
Why Do UR and PA Show Different Numbers for the Same Page?
This is the question most SEO professionals ask when they first compare the two metrics side by side. A page might show UR 45 in Ahrefs and PA 28 in Moz — or the reverse.
Several factors cause these discrepancies:
Different crawl indexes. Ahrefs and Moz both crawl the web, but they index different pages and update at different frequencies. Ahrefs often discovers new links faster — sometimes within days. Moz updates monthly. A new backlink to a page might appear in Ahrefs UR immediately but not show in Moz PA for several weeks.
Different link databases. Each tool has its own list of backlinks. A link that Ahrefs has found may not be in Moz’s index, and vice versa. The same page may genuinely have a different-looking backlink profile depending on which tool you check.
UR counts internal links more prominently. Ahrefs explicitly factors internal link structure into UR. A page that receives heavy internal linking from high-UR pages on its own site can show a strong UR even with relatively few external backlinks. Moz also uses internal links in PA, but the weighting differs.
PA includes spam penalization; UR does not. If a page has attracted many spammy links, Moz’s PA will penalize the score through its spam detection system. Ahrefs’ UR calculates the raw link power without applying the same spam filter. A page with lots of low-quality backlinks might show higher UR than PA for this reason.
Different machine learning models. PA was built to predict Google rankings. UR was built to measure link power. A page optimized for ranking but with modest link volume might have lower UR and higher PA. A heavily linked page with a toxic link profile might have high UR and low PA.
Which Metric Is More Accurate?
Neither is universally “more accurate” — they are accurate at measuring different things.
UR is more accurate for measuring raw link power. If you want to know how much link equity a specific page carries — for link building decisions, internal linking strategy, or comparing page-level authority across sites — UR is the more direct measurement.
PA is more accurate for predicting ranking potential. If you want to know how likely a page is to rank for a competitive keyword, PA’s machine learning approach — trained on actual Google data and incorporating spam detection — is the more relevant signal.
In practice, most professional SEOs check both when making important decisions. If UR is strong but PA is weak, the page likely has link power but a problematic link profile. If PA is strong but UR is modest, the page has clean, well-distributed authority that translates well to rankings.
UR Score Ranges — What They Mean in Practice
| UR Score | What It Indicates |
|---|---|
| 0 – 10 | Brand new or barely linked page |
| 10 – 25 | Low link authority — typical for newer content |
| 25 – 40 | Moderate — some quality links, competitive in easier niches |
| 40 – 55 | Strong — well-linked page, competitive in most niches |
| 55 – 70 | Very strong — significant external backlink profile |
| 70 – 85 | Exceptional — top pages on major publications |
| 85 – 100 | Elite — Wikipedia articles, viral news pieces, major government pages |
PA Score Ranges — What They Mean in Practice
| PA Score | What It Indicates |
|---|---|
| 1 – 10 | New page with minimal links |
| 10 – 25 | Low ranking potential — limited backlink profile |
| 25 – 40 | Moderate — can rank for lower-competition keywords |
| 40 – 55 | Strong — competitive for medium-difficulty keywords |
| 55 – 70 | Very strong — top pages on authoritative sites |
| 70 – 100 | Exceptional — major publications, viral resources |
When to Use UR vs PA in Your SEO Work
Use URL Rating (UR) when:
- Identifying which pages on a competitor’s site have the most link authority
- Deciding which pages to target for link building (linking to a high-UR page on your own site helps it transfer equity to linked pages)
- Evaluating the link power of a potential guest post page (not just the domain)
- Analyzing internal link equity distribution across your own site
- Checking whether a page you want a backlink from carries real link power
Use Page Authority (PA) when:
- Estimating how well a specific page will rank for a target keyword
- Comparing your page’s ranking potential against top-ranking competitor pages
- Tracking improvement in your most important pages’ authority over time
- Evaluating whether a linking page is clean enough (spam-free) to be worth pursuing
- Reporting page-level SEO progress to clients or stakeholders
Use both together when:
- Making a final decision on a guest post target — check UR for link power, PA for spam cleanliness
- Auditing the authority of your own site’s key pages
- Competitive analysis where you want the full picture of a rival page’s strength
Practical Example — Reading Both Metrics Together
Imagine you are evaluating two pages as guest post targets:
Page A: UR 52, PA 18. This page has strong raw link power (many links from authoritative sources) but weak ranking prediction. This combination often indicates the page has received many links from spammy or low-quality sources — inflating UR while Moz’s spam detection suppresses PA. Proceed with caution and manually review the page’s actual backlink sources.
Page B: UR 31, PA 39. This page has moderate link power but strong ranking prediction. This indicates a clean, well-optimized page with good-quality backlinks — fewer in number but higher in genuine value. A link from this page is likely worth more for your real ranking performance than a link from Page A.
Page C: UR 48, PA 44. Both metrics are aligned and strong. This is the ideal combination — genuine link power that also translates into ranking performance. Prioritize outreach to pages like this.
Summary
- URL Rating (UR) is Ahrefs’ metric for measuring a page’s backlink strength — raw link power, 0 to 100
- Page Authority (PA) is Moz’s metric for predicting a page’s ranking potential — machine learning-based, 1 to 100
- They often show different numbers because they use different data sources, update at different speeds, and measure related but distinct things
- UR is better for link building and link power analysis
- PA is better for ranking predictions and evaluating link quality
- Use both together for the most complete picture of a page’s authority
Frequently Asked Questions (FAQ)
What is URL Rating (UR) in SEO?
URL Rating is an Ahrefs metric that measures the backlink strength of a specific web page. It scores pages from 0 to 100 on a logarithmic scale, where higher scores indicate more and stronger backlinks pointing to that URL. It is Ahrefs’ page-level authority metric, paired with Domain Rating (DR), which measures overall site strength.
What is the difference between URL Rating and Page Authority?
URL Rating (Ahrefs) measures the raw backlink strength of a page. Page Authority (Moz) predicts how likely a page is to rank in search results. UR is a mathematical link flow calculation. PA is a machine learning model trained on real Google ranking data that incorporates spam detection. They often show different scores for the same page because they use different methodologies and data sources.
Which is more reliable — UR or PA?
Both are reliable for what they measure. UR is more reliable for assessing raw link power. PA is more reliable for predicting actual search ranking potential because it incorporates spam detection and machine learning trained on Google data. For most ranking-related decisions, PA is the more useful signal. For link building analysis, UR often provides more granular, up-to-date data.
Why does a page show high UR but low PA?
This usually means the page has many backlinks from low-quality or spammy sources. Ahrefs’ UR counts the raw link power regardless of spam. Moz’s PA penalizes pages whose links come from spammy domains. High UR with low PA is a warning sign — it suggests the page’s link profile is not clean, and a backlink from it may not carry the value its UR implies.
Why does a page show high PA but low UR?
This typically means the page has fewer backlinks overall, but they come from high-quality, clean, relevant sources. PA rewards quality over quantity and is not inflated by spam links the way UR can be. A page with higher PA than UR is often a safer and more valuable link target than it might appear from Ahrefs alone.
How often does URL Rating update?
Ahrefs updates UR near real-time as it crawls the web. New backlinks to a page can be reflected in UR within days of being discovered by Ahrefs’ crawler. This makes UR more responsive to recent link building activity than PA, which updates monthly with Moz’s index refresh.
Does URL Rating count internal links?
Yes. Ahrefs includes internal links in its UR calculation, though they are weighted separately from external backlinks. A page that receives heavy internal linking from high-UR pages on the same site will see its UR benefit from those internal links. This means site architecture and internal linking strategy directly influence UR scores.
Should I use UR or PA to evaluate guest post sites?
Use both. Check UR to understand the raw link power of the specific page where your link will appear. Check PA to assess whether that page’s authority is clean and likely to translate into real ranking benefit. Also check the domain-level metrics — DR alongside UR from Ahrefs, and DA alongside PA from Moz — for a complete picture.
Can a page have UR 0?
Yes. A brand new page with no backlinks and no significant internal links will show UR 0 in Ahrefs. Once the page receives its first quality backlinks or internal links from stronger pages, the UR begins to rise. UR 0 is common for freshly published content that has not yet been discovered or linked to.
