AI Detector by Quillbot

Quillbot’s AI content detector is a tool used for analyzing text to check whether or not it was generated using AI writing software. It looks for writing patterns that are associated with AI, like repetitive or predictable phrases, and then gives a confidence score between 0 and 100% that states the likelihood of the text being AI or human written.

There are two major factors that sets apart Quillbot’s AI detector from other similar tools.

First, it distinguishes how the text was created using AI (whether it was entirely AI-written, entirely human-written, or human-written with some AI refinement). This way, you get a clearer understanding of how your text was created, rather than just told whether or not it was made with AI.

Second, feedback is provided for each section of your writing, so you will always have a clear understanding of which sentences and phrases are flagged for AI writing. This makes the editing process much simpler, as you can save time by focusing primarily on rewriting the flagged sections of your text.

QuillBot is independently evaluated on

RAID

• Up-to-date models: Keeps pace with the latest AI writing tools like ChatGPT as they evolve
• Broad model coverage: Detects content from all major AI systems including ChatGPT, Gemini, Claude, and Copilot
• Low false positive commitment: Built to avoid flagging human writing
• Multilingual support: Detects AI text across multiple languages

• Longer texts (300+ words) produce more reliable scores than short inputs
• Heavily paraphrased or lightly AI-edited content is harder to detect for any AI checker
• Formulaic human writing (academic definitions, legal copy, structured templates) can score higher than expected for any AI writing detector

Quillbot’s free AI detector is designed to analyze text generated by modern large language models (LLMs). This includes AI models like GPT-5, GPT-4, Claude, Gemini, ChatGPT, Llama, and other similar models. Since

AI models are always changing and evolving, Quillbot’s AI detector is regularly updated to account for newer AI models and versions. This allows the tool to stay more accurate and effective at spotting AI writing as technology advances.

All AI checkers present the risk of false positives, or incorrect identification of AI use. Heavily paraphrased writing and highly formulaic content, such as legal jargon or academic writing, is more likely to present a false positive.

Quillbot’s AI checker accounts for AI-refined text specifically, reducing false positives for text that was written by a human but edited with AI.

Educators should use AI checkers as one input in a wider conversation with students. Our free AI detector flags text that may be AI-generated. Use your best judgment when reviewing results. Never rely on AI detection alone to make decisions that could impact someone's career or academic standing.

Yes, Quillbot’s AI detector can be helpful for teachers by determining the likelihood of whether their students' writing was created using the help of AI writing tools.

Teachers use various different AI detectors for scanning and evaluating student assignments for AI. Quillbot’s AI detector is a great resource for educators to check their classroom work for AI, while also being useful for students who want to make sure their writing assignments are not flagged as being AI-written.

Yes. Quillbot’s AI checker can also help to determine if a piece of writing features a mix of both human and AI writing. Rather than just simply evaluating an entire text as a single block of writing, the tool examines writing patterns line-by-line, identifying and flagging specific sections as being AI-generated.

No. Quillbot’s AI detector can not verify whether a piece of writing was created by a human or original. The tool simply analyzes a piece of text and searches for common AI writing patterns and estimates the probability of it being created with the use of an AI writing tool.

Quillbot’s AI detector is specifically designed to detect AI-generated text. It doesn’t analyze images, videos, or other types of media. If you would like to check whether an image was AI-generated, you can use Quillbot's

AI Image Detector

Quillbot’s AI detector can benefit professionals across many different industries. Educators can use it for evaluating student assignments, while journalists and editors can screen drafts or submissions from other writers. SEO teams and digital marketers can use AI detectors to review web content prior to publishing and maintaining quality across their content pipelines. Researchers and technical writers can use the tool for reviewing reports or documentation, and enterprise teams can utilize it for managing internal or client-facing content.

No, the AI detector is solely used to detect AI writing. Quillbot has many other tools, including a

Grammar checker

No. Quillbot’s AI detector can help you to scan and find AI-written content within a piece of writing, but it does not scan text for plagiarism. Use our

Plagiarism Checker

Yes. Quillbot’s AI detector supports 20+ languages. This makes it useful for international teams, educators, and publishers working with multilingual writing. Supported languages include English, Spanish, French, Portuguese, and many others.

Yes. While Quillbot’s AI detector focuses on identifying common AI writing patterns within text, it also connects directly with Quillbot’s other writing tools to help refine your flagged content. If sections of text are identified as being likely written by AI, you can quickly improve or adjust the writing by using our integrated tools within the same workflow. For example, you can use Quillbot’s Humanizer tool to rewrite your flagged text sound more natural and align it with your own voice or use the Paraphraser to rewrite sentences to sound more original.

Our AI detector simply identifies and flags text that might be AI-generated, but it is not perfect. Use your best judgment when reviewing results. Never rely on an AI detector alone when making decisions that could impact someone's career or academic standing.

Yes. Quillbot plans to integrate its AI detector directly into Quillbot Chat and browser extensions. This will give users the ability to check text for AI-generated patterns without ever having to leave their primary writing space.