The technology behind Nano Banana Pro
How the model works, based on public documentation and sourced evidence.
Nano Banana Pro is the consumer name for Gemini 3 Pro Image, Google DeepMind's image generation and editing model released in November 2025. Unlike standalone text-to-image systems, it is built on the Gemini 3 Pro language model and inherits its reasoning and real-world knowledge, so it can plan a composition before rendering it. It can also ground prompts with Google Search to pull in factual data for things like infographics and diagrams.
Compared with the original Nano Banana (Gemini 2.5 Flash Image), the Pro model adds 2K and 4K output across multiple aspect ratios, markedly better text rendering in multiple languages, and support for up to 14 reference images while keeping up to 5 people consistent across shots. It also exposes studio-style controls: localized edits on selected regions, camera angle and focus changes, scene relighting such as day-to-night, and color grading. On Google's published benchmarks it leads competing models on text-to-image and image editing preference scores, while the Flash-tier model remains the faster, cheaper option.
Google openly documents where the model still fails: small faces, accurate spelling, and fine details can come out wrong, infographics can contain factual errors because the model may misinterpret data, and complex edits like day-to-night conversions can produce visual artifacts or disjointed scenes. Character consistency across images is strong but not guaranteed.
Every image is tagged with SynthID, Google's imperceptible digital watermark, and you can upload an image to the Gemini app to check whether it was made by Google AI. Images generated in the Gemini app, Vertex AI, and Google Ads also carry C2PA content credentials, cryptographically signed metadata that records the image's AI origin. Free and Pro tier images additionally show a visible Gemini sparkle watermark, which is removed for Ultra subscribers.