Can ChatGPT Detect AI Text?

🧠 Introduction

For educators, researchers, and content reviewers, one question appears constantly:

Can ChatGPT detect whether text was written by AI?

Many users paste text into ChatGPT and ask, “Did you write this?” or “Is this AI generated?”

However, most people do not realize that ChatGPT is not an AI detector, and it cannot reliably determine whether text is AI generated or human written.

In this article, we break down why ChatGPT cannot detect AI, what happened to OpenAI’s old classifier, and what tools you should use instead.

🏛️ OpenAI Once Had an AI Detector

In early 2023, OpenAI released a tool called the AI Classifier, designed to identify whether text was written by ChatGPT or another AI model.

However, the classifier was removed only a few months later because:

It was not reliable
It struggled to correctly identify AI generated text
It produced false positives, labeling human writing as AI
It only caught a small portion of AI content even in ideal cases

OpenAI publicly stated that the classifier was not fully reliable and that it is impossible to reliably detect all AI generated text.

❌ Why ChatGPT Cannot Detect AI Text

ChatGPT is a large language model, not an AI detection model.

Its job is to generate text, not analyze the statistical signals that detectors rely on.

When you ask ChatGPT, “Did an AI write this?” it does not scan for mathematical patterns.

Instead, it simply guesses based on style, tone, and patterns it has seen during training.

This is not reliable because:

AI writing can look extremely human
Human writing can look robotic or structured
It cannot analyze token-level perplexity and burstiness the way detectors do

🧪 How AI Detectors Work

AI detectors such as GPTZero, TwainGPT, Copyleaks, and Turnitin use statistical methods like:

Perplexity analysis
Burstiness measurement
Token distribution
Predictability scores
Machine learning classifiers

These systems analyze the statistical characteristics of the text, which is something ChatGPT cannot evaluate.

AI detectors are not perfect, but they operate using deeper NLP models than ChatGPT does when guessing.

This is why you should use an actual AI detector, not ChatGPT itself.

📚 Why Educators Ask ChatGPT Anyway

Many teachers, students, and managers paste text into ChatGPT because they assume:

ChatGPT can recognize its own writing
ChatGPT can tell if something “sounds like AI”
ChatGPT has built-in tools for detection

None of this is true.

ChatGPT is not designed for AI detection, and OpenAI has stated that reliable detection is extremely difficult, especially as models become more advanced.