Here are two examples of web apps that you let check if an image is generated by AI:
https://illuminarty.ai/en/
https://www.aiornot.com/
The issue is that these are not authoritative nor is anything I've discovered. You can easily trick them just by cropping the AI-generated image. https://bastyon.com/scottcbusiness?s=bfc05879891cf55c192eb40d025c32eb391902f63844d8c2d969ef9690004d0b&address=PLH8biT5rMdvE1zXFhsvNkzphVRK6cNM7p&ref=PTRSmcxmvzFXxgtMXh1Gj9V3yvFiUJVBu2
