Grammarly AI Checker: Does It Actually Detect ChatGPT Text? [2026 Test]

Grammarly AI Checker: Test Results

The Grammarly editing tool introduced a feature for checking the AI score due to the rise in AI-written content at schools and in offices. This is how good it really works.

How Grammarly's AI Checker Works

The Grammarly algorithm, like most algorithms in this class, assigns scores to text that indicate predictability in word usage and rhythm of the sentences. Higher scores indicate that the text reads more like LLMs and less like human writers.

Where Grammarly's Detector Falls Short

Two patterns stood out in testing:

• It ignores humanized AI text. A passage that has undergone humanization gets an extremely low score on Grammarly, even if the source material was written using an AI program.
• It can misinterpret structured human-written text. Technical reports and business documents received unexpectedly high scores.

What This Means If You Use ChatGPT for Writing

In case you are being monitored using Grammarly at work or at school, unedited ChatGPT text will get detected. In order to pass the check without being deceptive about how you have done it, you need to start by doing the same thing as you did for Turnitin and ZeroGPT.

The quickest way to reduce the AI score of your draft using Grammarly without damaging the argument and references is by submitting it to Humanize AI Pro in the academic mode.