With AI tools like ChatGPT, Jasper, and Copy.ai becoming mainstream, it’s now easier than ever to generate content in seconds. But this rise in AI writing brings a growing need to verify authorship, especially in schools, journalism, and content marketing.
AI content detectors help bridge this gap. They scan your text for language patterns, sentence structure, and word predictability to estimate whether the content was likely written by a human or a machine. From classrooms to newsrooms, these tools are becoming essential for maintaining authenticity and accountability.
Let’s dive into the top performers.
Key Uses of AI Content Detectors
- Ensures academic honesty in schools and universities
- Verifies content authenticity for brands and agencies
- Helps recruiters evaluate genuinely written applications
- Maintains editorial integrity in journalism and media
- Supports SEO by aligning with Google’s quality guidelines
List of Top AI Content Detectors
1. QuillBot AI Content Detector
Website: https://quillbot.com
Well-known for its grammar and paraphrasing tools, QuillBot also offers an AI Content Detector that’s great for quick, straightforward checks. It’s ideal for students, freelancers, and educators who want a second opinion on the originality of content. The tool is easy to use, just paste your text and it instantly gives a percentage-based result on whether it’s likely AI-written.
QuillBot improved its detection model to better differentiate between reworded AI content and original human text.
Key Features
- Lightweight and fast detection
- No sign-up required
- Shows AI likelihood in percentage
- Integrated with writing tools
Pricing:
- Free: $0
- Premium: $4.17/month/billed annually
2. Sapling AI Detector
Website: https://sapling.ai
Originally built as a writing assistant, Sapling has expanded into a powerful AI content detection platform. It’s best known for balancing simplicity with professional-grade analysis. With Sapling, users can paste any text into the detection dashboard and get a quick, probability-based score showing how likely it is to be AI-generated.
What makes Sapling stand out is its clarity. It doesn’t overwhelm users with overly technical jargon. Instead, it delivers readable results with visual cues, percentage breakdowns, and sentence-level analysis. It’s also integrated into platforms like Gmail, Zendesk, and other CRM tools, making it an excellent choice for business professionals.
As of 2025, Sapling has added multilingual detection capabilities and a Chrome extension for on-the-fly checks.
Key Features
- Text analysis with confidence scoring
- Sentence-by-sentence breakdown
- Integration with enterprise tools
- Supports multiple languages
- Real-time AI vs. human detection
Pricing:
- Free plan available
- Pro: $25/month
3. Winston AI
Website: https://gowinston.ai/
Designed with educators in mind, Winston AI is a trusted name in classrooms and academic circles. Whether you’re a high school teacher grading essays or a university administrator reviewing student submissions, Winston offers a clean, classroom-ready experience.
Users can upload PDFs, Word docs, and even scanned images of handwriting. The platform processes them quickly, scoring them on a scale and highlighting potentially AI-written sections. In 2025, Winston AI has added adaptive learning detection and multilingual support, making it more inclusive for global education environments.
It also stores test history for comparison, allowing instructors to flag patterns across submissions.
Key Features
- Upload support for PDFs and images
- Designed for academic writing formats
- Class-friendly dashboard
- Detailed scoring and highlight system
- Works across English, French, and more
Pricing:
- Starter: $12/month
- Pro: $19/month
4. Small SEO Tools AI Detector
Website: https://smallseotools.com/ai-content-detecto
Small SEO Tools is a popular free resource hub, and its AI Detector is a handy option for content creators, bloggers, and marketers. While it’s not as advanced as some paid tools, it offers a reliable scan that labels content as AI-generated, human-written, or mixed. The platform is especially useful for those already using its plagiarism or grammar checkers.
The AI detector was updated to support longer content inputs and detect GPT-4 level writing more accurately.
Key Features
- Simple and beginner-friendly
- No registration needed
- Works well with other SEO tools on the site
- Flags AI, human, or mixed content
Pricing:
- Free
5. ZeroGPT
Website: https://www.zerogpt.com
ZeroGPT is one of the most widely-used AI detectors available today, with millions of users across education, business, and creative industries. It’s particularly popular for its speed, language versatility, and user-friendly interface.
You simply paste your content, click “Detect,” and receive a paragraph-by-paragraph breakdown of AI likelihood. It also generates a summary report and highlights sentences based on prediction probability.
ZeroGPT supports more than 30 languages and is frequently used by non-native English speakers looking to validate AI use in translated or localized content. It continues to be updated regularly to keep up with evolving generative AI models.
Key Features
- Free, fast, and accurate analysis
- Multi-language support (30+)
- Paragraph and sentence-level analysis
- Summary confidence reports
- Useful for blogs, essays, and marketing copy
Pricing:
- Free version available
- Premium: $9.99/month
6. GPTZero
Website: https://gptzero.me
Born in academia, GPTZero quickly became a global name in AI content detection after its launch in early 2023. Developed by Princeton grad Edward Tian, GPTZero was designed to identify machine-written academic writing with accuracy and explainability.
In 2025, it remains a leader in burstiness and perplexity-based analysis. The platform assigns scores to indicate how unpredictable and varied a piece of writing is, traits generally associated with human authorship. It also highlights suspicious sections, helping reviewers drill down into problematic content.
GPTZero now supports file uploads, including .docx, .pdf, and .txt files, making it perfect for academic and editorial reviews.
Key Features
- Burstiness and perplexity metrics
- Sentence highlighting of AI-likely phrases
- Simple and intuitive UI
- Batch document uploads
- Trusted by schools and media outlets
Pricing:
- Individual: $10/month
- Educator Plan: $15/month
7. Copyleaks AI Detector
Website: https://copyleaks.com
Copyleaks began as a plagiarism checker but has since grown into one of the most advanced platforms for detecting AI-written text. Used by major educational institutions, publishers, and enterprises, Copyleaks offers unmatched depth and scalability.
Its standout feature is dual detection, it identifies both plagiarism and AI generation. That makes it ideal for content verification where originality and authorship are both essential. Copyleaks supports side-by-side document comparison, multiple language detection, and even integrates with learning management systems like Canvas and Blackboard.
In 2025, Copyleaks has introduced real-time collaboration and an upgraded API for developers building in-house detection tools.
Key Features
- Detects AI and plagiarism in one scan
- Document comparison mode
- LMS integrations and API support
- Real-time collaboration for teams
- Over 30 language options supported
Pricing:
- Education: $10/month
- Business: Custom plans available
8. Smodin AI Content Detection
Website: https://smodin.io
Smodin is known as a multi-functional AI writing tool that also includes a solid content detector. Unlike other platforms focused only on detection, Smodin offers rewriting, paraphrasing, summarizing, and citation assistance, all in one workspace.
Its AI detection engine assigns a percentage score indicating how likely the content was generated by AI. It also works across file types, letting users scan entire documents, presentations, and research papers. The detection tool is integrated into its broader suite, making it ideal for writers who want to verify and revise as they go.
In 2025, Smodin added expanded support for technical writing, offering better accuracy for scientific and research papers.
Key Features
- All-in-one writing platform with AI detection
- Text and file scanning (PDF, Word)
- AI probability scoring
- Tools for rewriting and citation
- Designed for student and academic users
Pricing:
- Basic: Free
- Essential: $8/month
- Productive: $15/month
9. Content at Scale AI Detector
Website: https://contentatscale.ai
Originally built as an SEO content platform, Content at Scale now offers one of the most advanced free AI content detection tools. It evaluates content using Natural Language Processing (NLP) models trained to spot ChatGPT and GPT-4-based writing. Its predictions are broken into color-coded blocks that show how “robotic” a sentence might sound.
The tool has improved its detection engine to handle longer content and perform at scale for agencies and publishers handling bulk content checks.
Key Features
- Color-coded sentence-level analysis
- Detection of GPT-3, GPT-4, Claude, and Gemini-based text
- Optimized for blog and SEO content
- API access for bulk analysis
Pricing:
- Free tool available on the website
- Pro Tools: Custom pricing for agencies
10. Writer AI Content Detector
Website: https://writer.com/ai-content-detector
Writer.com is an enterprise writing assistant that also offers a free AI content detector. The tool is lightweight and ideal for quick checks on short-form content. While it doesn’t offer deep paragraph-level analysis, it’s fast, clean, and easy to use, perfect for marketers and teams creating branded content.
Key Features
- Quick probability percentage
- Clean, ad-free interface
- Free browser tool
- Good for headlines, copy, and intros
Pricing:
- Free
11. Turnitin AI Writing Detection
Website: https://turnitin.com
Turnitin is already a gold standard in plagiarism detection, and its AI writing detector is now widely adopted in schools and universities across the globe. In 2025, it can scan essays and reports to differentiate between AI-written and human-written segments with color-coded markings and confidence scores.
It’s trusted by thousands of institutions and is continuously updated to match new AI model behaviors.
Key Features
- Integrated with plagiarism detection
- Institutional-level reporting
- Color-coded originality scores
- LMS integration
Pricing:
- Available to institutions via subscription
12. Crossplag AI Detector
Website: https://crossplag.com
Crossplag is gaining popularity for its simplicity and ease of integration with academic systems. The AI detector checks for sentence predictability and linguistic anomalies common in machine-written content. It’s especially helpful for universities working to ensure student submissions are original.
Crossplag offers better support for international institutions with new language compatibility and expanded dashboard features.
Key Features
- Designed for education
- Sentence-level AI probability detection
- Multilingual support
- API integration available
Pricing:
- Free limited plan
- Pro: Custom pricing for institutions
Conclusion
As AI tools become smarter, the line between human and machine-written content keeps getting blurrier. That’s why having a reliable AI content detector is more important than ever. Whether you’re reviewing student work, screening freelance submissions, or protecting your brand’s voice, these tools offer a practical way to stay in control.
They don’t just detect AI, they give you confidence in the content you publish or approve. Pick the tool that fits your needs, and stay a step ahead in this fast-changing digital world.
FAQs
What does an AI detector do?
It checks if content was written by a human or AI
Are these tools 100% accurate?
No, they give probability-based results.
Can they detect content in other languages?
Yes, many support multiple languages.
Is there a good free detector?
Yes, tools like ZeroGPT and Writer offer solid free versions
Can paraphrased AI content be flagged?
Some tools can catch it, but not always.
