Why Are Rankings Different on SEMrush Than Ahrefs? SEO Data Explained

• SEMrush and Ahrefs use different crawlers, keyword databases, and ranking algorithms, which naturally leads to discrepancies in reported positions.

• SEMrush tracks rankings at domain, subdomain, and page levels, integrates SERP features, and often provides more granular location-based and device-specific data.

• Ahrefs emphasizes URL-level rankings and backlink authority, which can result in different pages being reported as top-ranking for the same keyword.

• Update frequency matters: SEMrush updates daily for tracked keywords, while Ahrefs updates less often, causing temporary differences in rankings.

• Location, device, and SERP features (like snippets or local packs) affect rankings, and each tool measures them differently.

• Keyword cannibalization and database coverage can create inconsistencies, especially if multiple pages target the same keyword or certain keywords aren’t tracked by both tools.

• Rather than focusing on exact positions, monitor trends and use each tool for its strengths: SEMrush for local SEO and competitive analysis, Ahrefs for backlinks and URL-level insights.

If you’re an SEO professional, digital marketer, or website owner, you’ve probably noticed one frustrating thing: your keyword rankings on SEMrush don’t always match the numbers in Ahrefs. You might see your target keyword ranking at #5 on SEMrush but #8 on Ahrefs, and it can leave you scratching your head.

So, why are rankings different on SEMrush than Ahrefs? In this article, we’ll break it down, explain the key differences in data and methodology, and show you how to make sense of it all.

Understanding Ranking Discrepancies

Before we dive into specifics, it’s important to understand that no SEO tool can track “perfect” rankings. Every tool collects and analyzes data differently. SEMrush and Ahrefs are both powerful, but they are built on different foundations.

Here are the main reasons why rankings differ between these two platforms:

• Data collection methods: Each tool crawls the web differently, which can result in variations.

• Keyword databases: SEMrush and Ahrefs maintain separate keyword databases that may have different search volumes and keyword sets.

• Rank tracking algorithms: The way each tool calculates position can vary, especially for local, mobile, or personalized results.

• Update frequency: SEMrush and Ahrefs update their data at different intervals. One might reflect changes sooner than the other.

How Do SEMrush and Ahrefs Track Rankings?

Understanding how SEMrush and Ahrefs track rankings is key to knowing why their results often differ. Each platform has its own approach to collecting, analyzing, and reporting SEO data, and the differences can explain why the same keyword might rank differently in each tool. Let’s break it down.

SEMrush Ranking System

SEMrush tracks rankings using a multi-layered approach designed to give a comprehensive view of your keyword performance:

1. Crawler-Based Analysis

SEMrush has its own web crawler that scans millions of websites across the internet. This crawler collects data on page content, backlinks, and metadata. By continuously scanning websites, SEMrush can detect changes in keyword usage, new content, and shifts in page authority.

2. Google SERP Snapshots

SEMrush doesn’t rely solely on its crawler. It also takes periodic snapshots of Google’s search engine results pages (SERPs) for tracked keywords. These snapshots allow SEMrush to monitor real-world rankings as they appear to users in specific locations. This is particularly useful for tracking competitive keywords in local markets or specific industries.

3. Historical Keyword Data

SEMrush maintains historical data for millions of keywords. This allows users to see trends over time, such as ranking improvements, seasonal fluctuations, or sudden drops. Historical data can provide context for ranking changes that might look alarming in a single snapshot but are normal over time.

4. Position Tracking Features

SEMrush offers a flexible position tracking tool that allows you to monitor keyword rankings at multiple levels: domain, subdomain, or specific pages. You can also track rankings for particular devices (desktop vs. mobile) or locations (cities, regions, countries). This granularity can result in differences compared to Ahrefs if you’re not comparing like-for-like settings.

5. SERP Feature Integration

SEMrush factors in Google’s SERP features like featured snippets, local packs, and video results when reporting rankings. Depending on the keyword and competition, a page might appear as #1 in SEMrush because it owns a featured snippet, even if it ranks #2 in standard SERP positions.

Ahrefs Ranking System

Ahrefs approaches rank tracking differently, with a strong emphasis on URL-level data and backlink authority:

1. AhrefsBot Crawler

Ahrefs uses its own crawler, AhrefsBot, which is particularly known for building one of the largest backlink indexes in the world. While it also scans website content, its focus is heavily skewed toward link analysis. This means that Ahrefs’ ranking data often reflects not just keyword usage but also the authority and strength of the pages linking to it.

2. Keyword Database and Tracking

Ahrefs relies on a proprietary keyword database to track rankings. This database can differ significantly from SEMrush’s, meaning some keywords may exist in one tool and not the other. The search volumes, difficulty scores, and click-through potential are all estimated differently, which can influence the reported ranking positions.

3. URL-Level Emphasis

Unlike SEMrush, which can report rankings at the domain or subdomain level, Ahrefs emphasizes URL-level ranking. This means that Ahrefs tracks the performance of individual pages for specific keywords rather than the domain as a whole. If multiple pages target the same keyword, Ahrefs will assign the ranking to the page with the highest perceived authority, which might differ from SEMrush’s domain-level ranking.

4. SERP Feature Consideration

Ahrefs also takes SERP features into account, but its methodology may count only traditional organic positions or weight featured snippets differently. This can lead to discrepancies, especially for keywords with rich results.

5. Data Update Frequency

Ahrefs updates its ranking data periodically, but the frequency may not match SEMrush’s daily updates. If a keyword has recently moved up or down, Ahrefs might lag slightly behind SEMrush in reporting the change.

Key Differences Summarized

To make it simple, here’s a side-by-side view of why SEMrush and Ahrefs can give different ranking numbers:

• Crawling Focus: SEMrush scans content and SERPs broadly, Ahrefs emphasizes backlink authority.

• Keyword Database: Each tool maintains a different set of tracked keywords and search volume data.

• Level of Tracking: SEMrush tracks domain, subdomain, or page; Ahrefs primarily tracks individual URLs.

• SERP Features: Both account for features differently, affecting how rankings are reported.

• Update Frequency: SEMrush tends to update daily for tracked keywords, while Ahrefs updates less frequently.

These differences mean it’s completely normal to see a keyword ranked #5 in SEMrush but #8 in Ahrefs, even for the exact same page. The tools are essentially giving you different perspectives on the same SEO landscape.

Are SEMrush Rankings More Accurate Than Ahrefs?

This is a common question and one without a clear-cut answer. Accuracy often depends on your goals and the type of SEO you’re tracking.

• SEMrush may offer more reliable local ranking data because it allows region-specific tracking.

• Ahrefs can be more accurate for backlink-driven keywords since its crawler excels at indexing link relationships.

Instead of thinking in terms of “better” or “worse,” consider each tool as offering different perspectives on your SEO performance.

How Often Do SEMrush and Ahrefs Update Rankings?

Update frequency is a major factor in discrepancies.

• SEMrush: Updates ranking data daily for tracked keywords, but its database may take longer to reflect new keywords or pages.

• Ahrefs: Updates its rankings less frequently but often provides a more consistent historical trend.

This means a keyword could jump a few spots in SEMrush before Ahrefs catches up. If you’re monitoring a recent SEO campaign, you might see mismatched results simply because the tools are working on different timelines.

Do Location and Device Affect Rankings?

Yes. One reason rankings differ is that SEMrush and Ahrefs may use different default settings for location and device tracking.

• Local SEO tracking: SEMrush allows you to track cities, states, or countries specifically. Ahrefs focuses more on global rankings by default.

• Device differences: Google ranks mobile and desktop separately. SEMrush often provides options for both, while Ahrefs defaults to desktop unless specified.

If you’re targeting local customers or mobile users, always double-check your rank tracking settings.

How Keyword Databases Influence Rankings

Your chosen keywords may also contribute to the discrepancies. Both SEMrush and Ahrefs maintain massive keyword databases, but the databases are not identical.

• Keyword coverage: Some keywords may exist in SEMrush but not in Ahrefs and vice versa.

• Search volume differences: Tools estimate search volume differently, affecting perceived keyword importance.

• Missed keywords: If a keyword isn’t in the database of one tool, it might not track it accurately.

Understanding these differences helps explain why one tool shows a keyword ranking higher than the other.

Algorithm Differences

Another major reason why rankings vary is the algorithm used by each platform.

• SEMrush relies on its own SERP tracking algorithm, which considers click-through rates, search intent, and historical trends.

• Ahrefs focuses on URL authority, backlink profile, and SERP volatility when calculating rank positions.

Because algorithms weigh different factors, minor variations in rankings are expected.

Can Keyword Cannibalization Affect Tool Rankings?

Absolutely. If multiple pages target the same keyword, it can confuse both SEMrush and Ahrefs.

• SEMrush might report the page with the highest CTR as ranking #1.

• Ahrefs might report the page with the strongest backlink profile as #1.

This means different tools may assign the top spot to different pages on the same website.

How SERP Features Influence Rankings

Google’s search results now include snippets, local packs, videos, and more. These SERP features can cause discrepancies:

• Tools may or may not consider featured snippets or knowledge panels when ranking keywords.

• A keyword with a snippet might show as #1 in SEMrush but #3 in Ahrefs if one tool counts the snippet as a ranking position.

Understanding SERP features can help explain the gaps you see between tools.

Can You Reconcile SEMrush and Ahrefs Rankings?

Yes, but it requires some effort. Here’s how:

• Set the same location and device parameters in both tools.

• Focus on URL-level tracking rather than domain-level tracking.

• Cross-check keywords to make sure both tools are tracking the same set.

• Track trends, not exact positions: Rankings fluctuate daily; trends give a better picture.

Remember, these tools are better for strategic insights than for exact precision.

Tips to Make the Most of SEMrush and Ahrefs

Even with discrepancies, both tools provide immense value. Here’s how to maximize their utility:

• Use SEMrush for local SEO campaigns and competitive analysis.

• Use Ahrefs for backlink insights and content gap analysis.

• Compare trends across both tools instead of obsessing over exact numbers.

• Export ranking data regularly to identify consistent patterns.

The combination of SEMrush and Ahrefs gives you a 360-degree view of your SEO performance.

Common Misconceptions About Ranking Differences

Some marketers assume one tool is “lying,” but that’s rarely the case. Here are common myths:

• Myth 1: Rankings should always match – False. Tools have different databases, algorithms, and update frequencies.

• Myth 2: SEMrush is better than Ahrefs – Not necessarily. Both have strengths and weaknesses depending on your focus.

• Myth 3: Fluctuations mean SEO failure – Minor differences are normal and usually inconsequential.

Recognizing these misconceptions will prevent unnecessary stress and misinterpretation.

How to Choose Which Tool to Trust

Ultimately, it depends on your goals:

• For tracking content performance, SEMrush may offer more contextual insights.

• For analyzing backlinks and authority, Ahrefs might be more reliable.

• For competitor research, using both tools can give you complementary perspectives.

Instead of choosing one over the other, think about which tool answers your most pressing SEO questions.

The Bottom Line

So, why are rankings different on SEMrush than Ahrefs? The answer is multi-faceted: it’s about databases, crawling methods, algorithms, location settings, and SERP interpretation. No tool can perfectly match Google’s exact rankings, but both SEMrush and Ahrefs offer valuable insights.

By understanding the differences and focusing on trends rather than exact positions, you can leverage both tools to optimize your SEO strategy effectively.

Remember, SEO isn’t about obsessing over one or two spots on a ranking report—it’s about identifying opportunities, improving your content, and tracking long-term growth.

Use SEMrush for local and competitive analysis, Ahrefs for backlink intelligence, and combine insights to make smarter decisions. The small differences in ranking numbers aren’t mistakes—they’re reflections of different perspectives on your website’s performance.