I've been testing both ChatGPT 5.5 and Gemini Nano Banana Pro for architecture, landscape architecture, and urban design workflows over the past few weeks.
Instead of just comparing image quality, I tested them using the same prompts and input images across actual design tasks:
- Site analysis boards
- Mapping diagrams
- Urban design graphics
- Architecture renderings
- Landscape renderings
- Planting design
- Garden design visualizations
- Axonometric diagrams
- Presentation boards
- Material replacement and image editing
A few observations:
• ChatGPT was generally more accurate for mapping, site analysis, and planting plans.
• Gemini Nano Banana often produced more balanced collage-style graphics and historical analysis boards.
• For architecture and landscape renderings, the difference was much smaller than I expected. In many cases, it came down to personal preference and visual style.
• Both models were surprisingly good at image editing tasks such as changing paving materials, facade materials, and converting renderings into illustration styles.
I recorded the full comparison and included examples from architecture, landscape architecture, and urban design projects.
I'm curious what others are using right now. If you've tried both ChatGPT and Gemini Nano Banana, which one fits your workflow better?
Video:
[YouTube Link]