Generative AI content creation tools are becoming more popular. However, it's now more important than ever to tell the difference between human-written content and artificial text. Spotting AI-written content with AI content detector tools is key to maintaining originality and authenticity in your work.
In this post, we’ll put some of the top AI content detection tools to the test. This article evaluates how effectively each tool identifies AI-written text, using a sample that is 74.36% AI-generated.
Let’s see which tools come out on top when it comes to pinpointing AI-generated content!
How will we put these AI Content Detector Tools to the test?
The tools tested include Surfer AI Content Detector, ZeroGPT, QuillBot's AI Content Detector, Originality.ai, Undetectable.ai, Grammarly's AI Detector, and Scribbr.
Each of these tools claims to help identify AI-generated text, but how do they perform when put to the test? Let's dive into the results.
This is the same text we will be using in each test 👇. 74.36% of the text was generated by AI.
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8 Best Free AI Content Detector Tools Reviewed
- Surfer AI Content Detector
- ZeroGPT AI Content Detector
- QuillBot's AI Content Detector
- Originality.ai
- Undetectable.ai
- AI Detector by Grammarly
- Scribbr
- StoryChief
1. Surfer AI Content Detector
SurferSEO has developed a tool designed to assist content creators in verifying whether their writing is human-generated or AI-driven. This popular tool is particularly beneficial for those in SEO and marketing who need high-quality, original content to achieve better rankings.
The test:
Test Results:
- Result: 1% AI-generated
- Conclusion: Surfer AI drastically underestimated the amount of AI-generated content in the test. This result suggests that Surfer AI may not be reliable for detecting AI-written text in this scenario.
2. ZeroGPT AI Content Detector
ZeroGPT specializes in identifying AI-written text with a user-friendly interface. Educators, businesses, and writers widely use it to ensure their content meets originality standards and avoids AI-related issues.
The test:
Test Results:
- Result: 19.36% AI-generated
- Conclusion: ZeroGPT’s result is closer than Surfer AI’s, but it still falls short compared to other tools. It seems to underestimate AI content but still does a better job than some other detectors.
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3. QuillBot's AI Content Detector
QuillBot’s AI detection tool works alongside its paraphrasing and writing features. It helps users evaluate whether their text has AI elements, making it a valuable resource for writers, educators, and researchers.
The test:
Test Results:
- Result: 63% AI-generated
- Conclusion: QuillBot’s result is the closest to the original estimate of 74.36%, making it one of the most accurate tools for identifying AI-generated content in this test. Its moderate level of detection seems reliable and consistent.
4. Originality.ai
Originality.ai actively assists content creators, marketers, and educators in detecting AI-generated text to ensure content originality. It focuses on identifying plagiarism and AI-written material, making it a useful resource for anyone who needs to maintain content authenticity.
Test Results:
- Result: 98% confident the text is original
- Conclusion: Originality.ai's result was extremely inaccurate for this test. It overestimated the originality of the text, making it unreliable for detecting AI-generated content in this case.
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5. Undetectable.ai
Focused on ensuring AI-generated content appears human-like, Undetectable.ai evaluates the text against detection algorithms and offers guidance on how to make content undetectable.
The test:
Test Results:
- Result: Claims the text is human/original, but does not provide a percentage.
- Conclusion: The lack of a concrete percentage makes Undetectable.ai less useful for this kind of test. The vague results make it hard to assess how accurately it identifies AI-generated text.
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6. AI Detector by Grammarly
Grammarly integrates this AI detector into its platform, flagging AI-generated content while also offering grammar, tone, and clarity suggestions for polished writing.
The test:
Test Results:
- Result: 33% AI-generated
- Conclusion: Grammarly’s tool showed moderate effectiveness, but it still significantly underestimated the AI content compared to the original estimate. It might be useful for quick checks, but its accuracy could be improved.
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7. Scribbr
Designed with students and academics in mind, Scribbr’s AI detection tool helps ensure the originality of research papers, essays, and academic writing. It’s an essential tool for avoiding plagiarism and maintaining integrity in scholarly work.
The test:
Test Results:
- Result: 63% AI-generated
- Conclusion: Scribbr’s result aligns with QuillBot’s and is among the most accurate of the tools tested, showing a close match to the original AI estimate.
8. StoryChief - Best AI Paraphraser
StoryChief is a content marketing platform designed for businesses and marketers to streamline content creation and distribution. It offers tools for collaboration, SEO optimization, and social media sharing, with an AI paraphrasing feature that helps rewrite content while keeping it professional and relevant.
While StoryChief does not have an AI content detection tool, it shines in another area: paraphrasing. In a separate comparison, StoryChief was named the best tool for paraphrasing.
Paraphrasing test:
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Test Results:
- Result: Best paraphrasing tool out of 5 tools tested. “StoryChief and PrePostSEO are the most balanced in terms of clarity and professionalism, with StoryChief being more readable and natural.”
- Conclusion: While StoryChief does not have an AI content detection tool, it shines in another paraphrasing, making your content sound less robotic.
TL;DR: What is the best AI Content Detector Tool?
Based on the test, QuillBot's AI Content Detector and Scribbr are the top choices for spotting AI-generated content. They gave results closest to the original 74.36% AI-generated estimate, showing better accuracy and reliability than other tools.
Key observations:
- Tools like QuillBot and Scribbr are the most consistent with the initial AI-generated estimate, suggesting they are more accurate in this specific test.
- StoryChief, while not an AI content detector, excels in paraphrasing. In a separate test, StoryChief was noted for its high-quality output, while tools like Spinbot and Paraphraser.io could improve the clarity and quality of their paraphrases.
- Originality.ai and Undetectable.ai had trouble detecting AI content, either labeling it as mostly human-generated text or giving unclear results.
- Surfer AI and ZeroGPT missed a lot of the AI content, showing inconsistent performance.
