We recently launched our new AI detector. For almost any webpage, you can analyze the likelihood that AI was used to create it, highlight AI-generated sections of text, and even identify the specific AI models used to create the text.
There are tons of AI detectors available. And, while ours is the only one that can also show you any webpage’s backlinks and estimated search traffic, how the page content has changed over time, and how it performs relative to other pages…
…we still wanted to know how Ahrefs’ AI detector compares to other popular detectors. So we tested it.
Interestingly, false positives were not a big issue. Only 2/24 tests run on human-written content incorrectly flagged the text sample as AI-generated. All the AI detectors struggled the most with the hybrid human/AI content (for reasons explained below).
In the table below, you can see the actual AI content of each test article, followed by each tool’s analysis:
Actual AI% | Ahrefs | Copyleaks | GPTZero | Originality.ai | Scribbr | ZeroGPT | Grammarly | Writer |
---|---|---|---|---|---|---|---|---|
100% | 100% | 100% | 92% | 100% | 94% | 99.62% | 59% | 24% |
100% | 100% | 100% | 100% | 100% | 100% | 98.99% | 57% | 23% |
100% | 86% | 83.8% | 52% | 64% | 0% | 67.76% | 7% | 15% |
0% | 2% | 0% | 0% | 0% | 0% | 0% | 0% | 2% |
0% | 6% | 0% | 0% | 0% | 0% | 2.76% | 0% | 2% |
0% | 0% | 0% | 4% | 0% | 0% | 91.69% | 0% | 27% |
50% | 13% | 46.4% | 42% | 46% | 0% | 39.06% | 0% | 0% |
50% | 32% | 0% | 28% | 4% | 0% | 29.4% | 0% | 5% |
50% | 70% | 100% | 86% | 4% | 83% | 83.21% | 0% | 6% |
Score | 13 | 13 | 12 | 12 | 10 | 9 | 6 | 4 |
Ahrefs’ AI Detector
Score: 13/18
URL: https://ahrefs.com/writing-tools/ai-content-detector
Ahrefs AI Detector showed good accuracy across the board, with no false positives for human-written content, and good detection for AI content. It also managed to detect the specific model types used for the AI content: GPT-4o and Meta’s Llama.
By my criteria, it failed one out of nine tests, struggling to identify AI content that was blended with human writing. This is a known limitation of all AI detection tools (more on that below), and was true of all detection models.
Ahrefs AI detector is based on our own proprietary detection model, trained on a huge amount of web content. It’s unique among AI detectors because you can use it in conjunction with tons of other Ahrefs data points to see how content actually performs.
You can use Ahrefs’ AI detector to see:
- Which AI models are the best for creating high-quality content.
- How often your competitors publish AI content, and which models they use.
- How much AI content is present in a particular SERP, and how much effort you might need to invest to rank.
- How organic performance metrics correlate with different levels of AI use, like search traffic, keyword rankings, and backlinks.
- Whether AI content use correlates with traffic drops on particular pages or in particular subfolders.
How to use Ahrefs’ AI detector
Start by heading to Site Explorer and pasting the URL you want to analyse. From there:
- Click the Page inspect report tab in the left sidebar.
- Choose the AI Detector tab.
- See your AI content level report in the right sidebar. Text that our model has detected as likely AI-generated will be color-coded according to the colors in the pie chart
In this example, our AI detector has found a section of my blog post that I used ChatGPT’s GPT-4o model to generate:
From there, you can also see how the page content has changed over time, how many backlinks it has earned, how many keywords it ranks for, how much estimated organic traffic it receives…
You can also test out the model via our free AI content detector page. We’re also adding bulk AI content detection to the Top pages report in Site Explorer (coming soon).
Copyleaks
Score: 13/18
URL: https://copyleaks.com/ai-content-detector
Copyleaks matched the top score, showing solid detection ability across both extremes of AI content. It proved especially effective at catching obvious AI writing, though it occasionally faltered in mixed or borderline passages.
GPTZero
Score: 12/18
URL: https://gptzero.me
GPTZero offered reliable results overall, with a clear strength in catching high-percentage AI content. However, it sometimes hesitated in assigning confident AI probabilities to mid-range or hybrid examples, slightly affecting its total accuracy.
Originality.ai
Score: 12/18
URL: https://originality.ai/ai-checker
Originality.ai performed well in most cases, accurately flagging AI-heavy text but showing a tendency to overestimate human authorship when faced with subtle or well-edited AI-generated material.
Scribbr
Score: 10/18
URL: https://www.scribbr.com/ai-detector/
Scribbr landed in the middle of the pack, handling clear-cut AI content reasonably well but displaying a drop in performance on more nuanced pieces, where its predictions tended to be inconsistent or overly cautious.
ZeroGPT
Score: 9/18
URL: https://zerogpt.com
ZeroGPT’s performance was uneven—it occasionally nailed high-AI content but frequently misclassified partial-AI and low-AI samples. The tool’s sensitivity seemed skewed toward extremes, resulting in a less balanced profile.
Grammarly
Score: 6/18
URL: https://www.grammarly.com/ai-detector
Grammarly’s free AI detector struggled with accurate AI detection, offering low-confidence or inaccurate predictions in many cases. It often failed to recognize clear signs of AI authorship and was unreliable on mixed or borderline content.
Writer
Score: 4/18
URL: https://writer.com/ai-content-detector/
Writer’s free AI detector scored the lowest, frequently misidentifying or entirely missing AI-generated material. It lacked precision across the board and provided little useful signal even when dealing with content that was 100% AI-written.
Further reading
It’s clear that AI content isn’t going away, so it’s a good idea to use a tool like Ahrefs’ AI detector to understand how AI content impacts your website performance. To get started, head to Site Explorer.
Similar Posts
12 Link Builders Share Strategies That Work in 2024
I asked 12 SEOs for the link building strategy that’s working best for them right now. Here are the tactics they shared, how to do them, and tips for success. find their email address and reach out to them. Here’s an example email Jason used: I don’t recommend copying Jason’s email word for word, but here’s his and…
Drupal CMS Guide Update: The Challenge of Documenting a Fast-Moving Open Source Product
Monday, Jan. 13th – 2 days before the Drupal CMS product launch I sat down at my desk this morning with the intent of working on creating screenshots for the documentation related to finding and installing recipes using the Drupal CMS UI. These images will accompany text that was written about a month ago, and…
10 Fastest WordPress Hosting Provider In 2025 – [Reviewed]
WordPress has become one of the most used and renowned CMS platforms worldwide over the years. WordPress has enough features and works almost perfectly. It is a CMS from which a user may need nothing more and nothing less. Whether you’re a beginner or an advanced-level user, this platform is meant for you! It’s best…
Between Buzz and Reality: The CTEM Conversation We All Need
Jun 24, 2025Ravie LakshmananThreat Exposure Management I had the honor of hosting the first episode of the Xposure Podcast live from Xposure Summit 2025. And I couldn’t have asked for a better kickoff panel: three cybersecurity leaders who don’t just talk security, they live it. Let me introduce them. Alex Delay, CISO at IDB Bank,…
10 Best Hostinger Alternative 2025, Sep | Top Competitors
When it comes to affordable web hosting services, Hostinger is often one of the first names that pops up. It’s budget-friendly, beginner-friendly, and offers a simple platform for individuals starting their online journey. However, when it comes to handling enterprise-level workloads that need powerful hosting solutions, the question comes, Can Hostinger provide big dedicated solutions?…
100 Most Cited Domains in Google’s AI Mode
Article Performance Data from Ahrefs Linking websites The number of websites linking to this post. Get the week’s best marketing content We analyzed our Brand Radar database of 5.5 million AI Mode queries to identify the domains that appear most often in Google’s AI Mode responses. These are the 100 most cited domains, along with…