Google has upgraded its Gemini image-generation technology with Nano Banana 2.1, intensifying competition with ChatGPT’s image-generation capabilities. In a hands-on comparison published by TechRadar on October 13, 2026, both tools produced impressive results, with differences emerging in image realism, text rendering and consistency.
The comparison suggests that choosing the better tool increasingly depends on the type of image a user wants to create.
1. Google Strengthens Its AI Image Generator
Nano Banana 2.1 is designed to improve visual quality, follow prompts more accurately and maintain consistency across multiple images. Google has also focused on clearer text rendering and more reliable image editing.
These improvements matter for users creating social media graphics, marketing materials, illustrations and other visual content. However, the latest upgrade does not automatically make Gemini superior to competing tools.
2. ChatGPT Keeps Pace With Realistic Images
TechRadar compared the two systems using identical prompts designed to test different image-generation capabilities. ChatGPT produced detailed scenes with realistic lighting and elaborate compositions.
In a test involving a Victorian greenhouse inside a glass snow globe during a thunderstorm, both generators created visually impressive results. ChatGPT delivered a richly detailed scene, while Gemini produced convincing reflections and a more restrained, natural-looking composition.
The results showed that both tools can handle complicated lighting and transparent surfaces, although their artistic interpretations differed.
3. Gemini Shows Strength in Text Rendering
AI image generators have historically struggled to reproduce exact words, particularly in posters and advertisements. The comparison tested this by asking both systems to create a retro-futuristic travel poster for Saturn’s moon Titan.
Gemini reproduced the requested wording and price correctly. ChatGPT generated a polished advertisement but introduced a spacing issue around the dollar sign and price.
This suggests that Gemini can be particularly useful when an image needs specific text. Still, results can vary depending on the prompt and generation.
4. Character Consistency Gives Gemini an Edge
The next test involved a four-panel comic featuring an orange fox wearing a green scarf. The character had to discover a key, unlock a door and enter a library while maintaining the same appearance.
Gemini produced a traditional comic-strip style with clear panels and consistent character details. ChatGPT created more elaborate, almost three-dimensional illustrations, but the fox’s proportions varied slightly between panels.
For creators developing comics, storyboards or recurring illustrated characters, consistency can be just as important as visual detail.
5. Both Models Make Mistakes With Complex Instructions
The final test asked the generators to create an overhead photograph containing several specific objects, including a dragon illustration, a north-pointing compass, three red wax seals, a blue gemstone and a pocket watch showing 3:15.
Both systems produced attractive compositions and included the requested objects. However, Gemini displayed the wrong time on the watch, showing 3:00 instead of 3:15.
The result highlights an important limitation: even advanced AI image generators may overlook small details when handling prompts with multiple requirements.
6. Which Image Generator Should You Choose?
The comparison does not establish a universal winner. Gemini showed advantages in text accuracy and character continuity, while ChatGPT delivered detailed, polished compositions in several tests.
The best option depends on the intended use. Gemini may appeal to creators who prioritise consistent characters and text-heavy designs, while ChatGPT remains a strong choice for realistic scenes and creative compositions.
Users should also inspect generated images before publishing them, particularly when they contain prices, labels, numbers or other information that must be accurate.
7. AI Image Generation Is Becoming More Competitive
The narrowing gap between these tools reflects rapid progress in generative AI. Image generators are becoming more useful for everyday creative work, from promotional graphics to illustrated stories and concept designs.
As both companies continue improving their models, differences in reliability, editing controls, access and cost may become as important as visual quality. For users, the competition offers more capable creative tools and greater flexibility.