7 Best AI Detection Tools to Spot AI-Generated Content

AI writing tools have become so advanced that their content can look like legit and convincing texts on almost any topic. However, this also poses a challenge in distinguishing between human-written and AI-generated texts.

Fortunately, there are many AI detection tools available that can help you with that. Because people should not use AI to cheat or fool others. In this blog post, we will introduce you to 7 of the best AI detection tools and how they work.

Table of Contents:

  • Turnitin
  • GPTZero
  • Hugging Face
  • Content At Scale
  • Originality.AI
  • Copyleaks
  • Kazan SEO


Turnitin’s AI writing detection is a new feature that has just been recently added to this tool. Turnitin uses artificial intelligence to analyze student writing and compare it to a large database of academic and other sources. It also generates reports that indicate how much of the work is original and how much is produced by AI. This helps educators to monitor academic integrity while promoting critical thinking among students.

Turnitin can currently identify content from the GPT-3 and GPT-3.5 language models, which includes ChatGPT. However, it is not yet able to detect content from GPT-4 or ChatGPT Plus.

However, the tool is not 100% accurate and may sometimes give false positives or miss some AI-generated text. Therefore, educators should not rely solely on the tool and use their own judgment as well.


GPTZero is a free alternative to Turnitin that is more popular among teachers and students. Similar to Turnitin, GPTZero uses AI to compare a piece of content to its data on both human-written text and AI-generated text. It can then determine how likely the content is to be written by AI.

GPTZero even though a free tool, can actually check content created by ChatGPT, GPT-4, GPT-3, Bard, Bing, and many other tools.

However, much like Turnitin, the result you get from GPTZero should be used for reference only as it has once classified that the US Constitution was written by AI. Therefore, you should not trust GPTZero blindly and always use your own common sense.

Hugging Face

Hugging Face’s AI detector is part of a platform and a community for artificial intelligence and data science that aims to democratize AI knowledge and assets.

Hugging Face AI detector is free and can identify content from all GPT models as well as other AI tools like BARD or Bing.

However, since AI detection is not Hugging Face’s main focus, its user interface is not very friendly or easy to use. Moreover, the result it gives is a simple yes or no answer to the question “Is this piece of content written by a human?” without much explanation or detail like some other tools.

Content At Scale

Content at Scale is an SEO content generation tool that also has an AI detection feature. This is one of the best free AI detection tools available right now. It can recognize content created by most of the major content-generation AI and provide a detailed report of what parts are AI-generated and what parts are not.

Content at Scale’s AI detector does not have the usual limitations of other “free” tools, such as limited usage per day or limited word count. (Technically, it does have a word limit, but it is 25,000 words, which is much higher than most AI detection tools.)


Originality.AI claims to be the most accurate AI detection tool on the market. It can not only detect AI-generated content but also check for plagiarism. It can even detect phrases that have been paraphrased by Quill bot.

This is why this might be the best tool for content marketers, SEOs, and website publishers who want to detect AI-generated content and protect their websites from Google AI content updates.


Copyleaks is the most accurate free AI detection tool you can find. After analyzing your content, Copyleaks will give you a percentage of how human-like each section of the content is. You can then identify the problem and target where you should make changes in your content and improve it accordingly.

However, Copyleaks is not completely free. It has a strict limit of 6,250 words scanned per day for the free plan. If you want to scan more text, you will have to pay for their paid plans.

Kazan SEO

Kazan SEO is an SEO toolkit that includes an AI content detection tool. This toolkit can help you generate content, research keywords, extract text from URLs, and optimize your content for co-relation.

But its detection tool is not that great. You have to put in at least 200 words to get good results and you can only check up to 400 words or 2,500 characters at a time which is not far below the normal standard for an AI detection tool.

How Do AI Detection Tools Work?

All these tools work in a similar way with a few minor differences. They look at different things in the text, like how predictable, probable, patterned, coherent, original, readable, emotional, toned, and personal it is. They compare the reader with a lot of human-written text and give it a score or a label to show how likely it is to be written by AI.

Some of them use machine learning models that learn from examples of texts written by humans and by AI and learn how to tell them apart based on their features.

And the two core concepts of this is largely based on burstiness and perplexity:

Burstiness: A predictable length and tempo to sentence structure.

Perplexity: A randomness to the words chosen in a sentence or collection of sentences.

Based on these two core principles, you can bypass AI detectors easily.

How Accurate Are AI Detection Tools?

Many AI detection tools say that their tools are “98% accurate” but we don’t think that’s true.

The accuracy of AI detection tools depends on many things, like the type and quality of the data, how complex and strong the algorithms are, how they measure and judge their results, and the topic and situation of the text. Different AI detection tools may be more or less accurate for different kinds of text and tasks.

According to Open AI, the AI classifier is not fully reliable, it is correct about 26% of the time, depending on the tool and the task.

Do We Have To Worry About AI Detection?

Not really. Since ChatGPT and other AIs are trained on huge amounts of human data that we can hardly imagine, the result that is they learned the best ways to communicate coherently and concisely, without compromising the content quality. This is why some well-written documents like the US Constitution were flagged as AI written.

AI detection tools are not there to stop or punish us for using AI for content creation. They are there to stop people from misusing the language model to create bad content that has no value for readers. As stated in Google’s guidance about AI-generated content:

“Appropriate use of AI or automation is not against our guidelines. This means that it is not used to generate content primarily to manipulate search rankings, which is against our spam policies.”