GPTZero AI Detector Review

GPTZero checks human or AI-written content with advanced features, API integration, and flexible pricing plans. Let’s have a look!

By: Steven Pinker, Published on: 2024-01-01, Last Updated: 09-01-2024

Reviewed by: Joanna Penn

Table of Contents

GPTZero is a tool designed to deal with the growing challenge of identifying AI-generated content. A student at Princeton, whose name was Edward Tian, created this tool. 

This tool helps to tell if something was written by a human or an AI. It’s specifically trained to identify ChatGPT, GPT-4, Bard, LLaMa, and various other AI models.

In this article, I’m going to review this AI detector. I’ll find out how it works for checking AI and how accurate it is. Before I start reviewing, let’s check the reviewing process.

Process of Reviewing 

I thoroughly tested the GPTZero to see how well it could tell whether the content was written by a human or generated by AI:

Step 1: Initial Evaluation

I began the review process by comparing human-written and AI-generated content to see if this AI checker could tell the difference.

Step 2: Precision and Reliability Test

In this step, I compared the accuracy of this tool to that of a human-written blog and an AI-generated piece. 

Step 3: Experimenting with Strategies

Finally, I tried various tricks to see if this AI detector could show AI-generated content as human-written. 

Checking How Well GPTZero Works

This tool takes a different approach compared to many AI content detection tools. It doesn't rely on a probability format. Instead, it offers a straightforward statement indicating AI plagiarism. However, it displays the perplexity score and the burstiness score.

Now, let’s begin to check the accuracy of GPTZero. I simply asked ChatGPT to generate a paragraph on coffee. 

ChatGPT instantly provided me with a paragraph of 96 words on this topic. Let’s see if this tool can detect its AI similarity.

ChatGPT Response

Therefore, I opened the tool and pasted my generated paragraph in the text box to check for AI plagiarism. Then I clicked on “Check Origin." Here is what it shows:

GPTZero results AI Written

This AI checker showed that the content was likely to be written by AI.

GPTZero writing analysis

Besides detecting AI, this tool also provides a writing analysis of that text. It showed that the burstiness, readability, and simplicity of the content were low. While the average sentence length was high. 

Now that I’ve tested this tool with AI content, it’s time for us to check what it will do with human-written content.

I wrote a paragraph on the same topic and inserted it into the AI checker. Here’s what it showed:

GPTZero results human Written

GPTZero showed that the content was likely to be written by a human.

Writing analysis

Moreover, the writing analysis of the text showed a low average sentence length. The burstiness, perplexity, and simplicity were high in the human-written content. 

I’ve tested this tool for both AI-generated content and human-written content. It gives accurate results, which means that it works well for finding AI similarities within the content.

Key Features 

GPTZero uses advanced algorithms like machine learning, dynamic programming, and quantum algorithms to tell the difference between human-written and AI-generated content. Let's discuss some of its features

1. It Highlights AI Written Text

It highlights the AI text so that you can identify which sentences have AI plagiarism. This makes it easier for you to understand how many sentences you need to improve or have AI similarities. 

2. Origin by GPTZero

This is a key feature. Origin is a Chrome extension that makes it super easy to browse the internet and check the AI-generated content. Plus, it can be used in Google Docs to create reports for editors or educational projects.

3. Human Writing Report

While you can check how many sentences have AI plagiarism and how many are human-written, you can download this data into a report. 

4. Perplexity Score

The AI detector provides you with a perplexity score against your provided content. This makes it easier for you to understand the amount of AI similarity in your content. The higher the perplexity score, the more likely it is to be human-written. 

5. Burstiness Score

It checks how sentences are structured and how humans mix up short and long sentences when they write. This score helps you correct the sentence structure of your content. 

6. API Integration

GPTZero provides its API so that someone can integrate it into their system or software. You can learn more about this by reaching out to their support team.

Price Plan

GPTZero comes with a free plan that covers up to 5,000 characters of text every month. But if you're a regular user who wants to check more text, there are three paid plans:

  1. Essential Plan: For $10 a month, this plan gives 150,000 words of text per month.
  2. Premium Plan: For $16 a month, this plan gives 300,000 words of text each month 
  3. Professional Plan: For $23 a month, this plan will give 500,000 words of text per month.

GPTZero Price Plan

Pros and Cons of GPTZero

Let’s find out some of its pros and cons.


  • It is clear and honest, as it tells you exactly how it works.
  • Have a user-friendly interface.
  • There's a free version that anyone can use without signing up. 
  • It can point out AI-written blogs, handle many files at once, and even have a special tool in Google Chrome.


  • Sometimes, it lacks accuracy.
  • It doesn’t support other languages except English.

Best For

GPT Zero offers versatile applications across various domains. 

  • In education, benefit from checking student assignments for originality. 
  • Researchers use it to verify the originality of papers and to make their research genuine. 
  • It aids recruiters by verifying resumes and cover letters to ensure candidates haven't used AI software.
  • For content creators, bloggers, and journalists to verify the authenticity of written materials. 


Here are some top alternative AI detectors to GPTZero that you can use:

  • Scribbr 
  • Duplichecker


GPTZero, made by student Edward Tian at Princeton, is awesome at spotting if the text is human-written or AI-generated. It's easy to use, but it can sometimes make mistakes and needs updates. Still, it's handy for students, researchers, recruiters, and content creators. With fair prices and an openness to integration, it's a useful tool all around.