AI Image Detection Accuracy Compared: ImageDetector.com vs NoteGPT

AI image generators aren't leaving obvious clues anymore  and that's exactly what makes this test worth running.

A year ago, spotting an AI-generated image was almost intuitive. The 6 fingers. Melting ears. 

Text that looked like it was designed by someone who had never seen the alphabet. That's not the case anymore.

Midjourney, ChatGPT, Gemini, Stable Diffusion, these tools have quietly closed the gap between "obviously AI" and "wait, is this real?" 

So the real question isn't whether AI images are getting better. They clearly are. 

The question is whether detectors are keeping pace.

That's what I wanted to find out. I ran ImageDetector and NoteGPT's image detection tool through six tests. 

Here's what I found.

What is ImageDetector.com?

ImageDetector is a free, dedicated AI image detector and the "dedicated" part is what sets the tone for everything else about it.

Rather than being tuned to one generator's output, it's built to recognize patterns across the major players, DALL·E, Nano Banana, Midjourney. 

There's no account to create, no paywall blocking basic use. 

You upload an image, it tells you whether it looks AI-generated or human-taken, and that's the whole product. 

Simple by design. 

What is NoteGPT?

NoteGPT is a genuinely useful AI platform. It summarizes videos, generates notes from lectures, answers questions about uploaded content, and helps students move through material faster. 

For that core use case, it works well and has built a real following.

Image detection is part of its broader toolkit, one of several features it's layered on top of that foundation. 

There's a free trial to get started, and the full experience unlocks inside NoteGPT's paid ecosystem alongside everything else the platform offers. 

Upload an image, get a result.

A Quick Note on Privacy

Both tools process images through their servers. If you're working with unpublished content, client materials, or anything sensitive, be careful about what you upload. 

What I Tested and Why

I ran six images through both tools under the same conditions.

Four were AI-generated  one each from ChatGPT (DALL·E), Gemini, Midjourney, and Stable Diffusion. 

Two were real photos taken on a phone: one completely unedited, one with cropped with basic edits applied.

The Actual Head to Head: ImageDetector vs NoteGPT

Test #1:  ChatGPT (DALL·E)

ImageDetector.com: Correctly flagged the image as AI-Generated
AI Likelihood Score: 99%

NoteGPT: Correctly flagged the image as AI-Generated
AI Likelihood Score: 99.72%

Test #2: Gemini (Nano Banana)

ImageDetector.com: Correctly flagged the image as AI-Generated
AI Likelihood Score: 99%

NoteGPT: Correctly flagged the image as AI-Generated
AI Likelihood Score: 100%

Test #3: Midjourney

ImageDetector.com: Correctly flagged the image as AI-Generated
AI Likelihood Score: 99%

NoteGPT: Incorrectly flagged the image as Human
AI Likelihood Score: 1.2%

Test #4: Stable Diffusion

ImageDetector.com: Correctly flagged the image as AI-Generated
AI Likelihood Score: 98%

NoteGPT: Correctly flagged the image as AI-Generated
AI Likelihood Score: 100%

Test #5: Real Photo (Raw)

ImageDetector.com: Correctly identified the image as Real
AI Likelihood Score: 41%

NoteGPT: Correctly identified the image as Real
AI Likelihood Score: 0.90%

Test #6: Real Photo (Cropped)

ImageDetector.com: Flagged the cropped photo as AI Generated
AI Likelihood Score: 76%

NoteGPT: Correctly identified the image as Real
AI Likelihood Score: 0.41%

Score Summary

Test	ImageDetector	NoteGPT
#1 ChatGPT	99%	99.72%
#2 Gemini	99%	100%
#3 Midjourney	99%	1.2%
#4 Stable Diffusion	98%	100%
#5 Real Photo (Raw)	41%	0.90%
#6 Real Photo (Cropped)	76%	0.41%
Correct Calls	5/6	5/6

Final Thoughts

Five out of six for both tools. 

That's not the blowout result you might expect going into a matchup between a dedicated detector and a platform add-on and that's what makes it interesting.

ImageDetector.com was consistent across every AI-generated image, hitting 98–99% confidence without flinching. 

But it stumbled on the cropped but real photo, flagging it as AI-generated at 76%. That's a meaningful false positive. 

Post-editing alone was enough to trip it up, which is worth knowing if edited images are part of your workflow.

NoteGPT's miss was on the other end. It completely whiffed on the Midjourney image returning just 1.2% when the correct answer was clearly AI. 

Midjourney's outputs are among the most polished in the space right now, and NoteGPT didn't come close to catching it. 

When the accuracy is this close, the tiebreaker comes down to what each tool gives you after the result. 

ImageDetector tells you the score and that's it. 

NoteGPT gives you a detailed breakdown of its analysis and you can download or share the full report too.

That's not a small thing. If you're a student, a researcher, or anyone who needs to show their work, a downloadable report is genuinely useful. 

As a result, NoteGPT is the one I'd reach for in this test.