Image generation with ChatGPT vs Nano Banana: Find out which one stands out

Comparing chatbots is nowadays a popular pastime, as many users ask the same question of different AI systems to find out which delivers the smartest and most reliable answer.

The same curiosity has now extended to AI image generation, an area long criticised for producing awkward, unrealistic visuals often labelled as “AI slop”.

Such images are flooding the internet, and blurred backgrounds, flawless faces and strange extra fingers have given them a poor reputation. But that's not the case with stock photos.

A massive change in stock image landscape has just emerged as OpenAI recently upgraded ChatGPT’s image generation model, positioning it as a stronger rival to Google’s Gemini Nano Banana Pro.

When tested, the most noticeable shift was realism. The heavy blur and artificial polish that once gave images away are far less common, making the results more usable for articles, advertisements and social media posts.

Using the same prompts, both systems were tested on practical scenarios. 

Comparing Nano Banana Pro and ChatGPT for stock image generation

For an image of someone listening to a podcast in an office, Nano Banana Pro delivered a more convincing result. Slight imperfections, such as mildly messy hair and a softer background, made the image feel closer to real life. On the other hand, ChatGPT’s version, while clean and fast to generate, appeared overly perfect and contained an element of artificiality.

When asked to create a promotional image of someone reading a book, Nano Banana Pro again leaned towards realism. ChatGPT’s output struggled with an unnatural, computer-generated feel, where lighting and poses looked staged rather than natural.

An area where ChatGPT outdid the other was when asked to generate a generic stock image for an article. Its output was usable, although somewhat fake, while Nano Banana Pro missed the mark entirely with an abstract, self-referential design.

In a final test that focused on leadership struggles, both tools produced familiar but uninspired office scenes, with Nano Banana Pro once again securing an additional notch on realism.

While AI image generation has advanced rapidly, neither of the two tools is perfect. Nano Banana Pro currently leads in realism, and ChatGPT closed the gap quickly. At the moment, it appears that the line between real and AI-generated images will soon disappear.