News
Google Launches Nano Banana 2.1: Image Model Goes 4K, Old Version Retires End of Month
On October 6, Google made image generation model Nano Banana 2.1 generally available, with up to 4K output and 14-reference-image blending. The previous Gemini 3.1 Flash Image shuts down October 29 — developers need to migrate soon.
What Happened
On October 6, Google moved image generation model Nano Banana 2.1 to general availability (GA). It succeeds Nano Banana 2 (officially Gemini 3.1 Flash Image), released this February. Google says the new model “surpasses the previous model in every way, with clear gains in visual design, mask editing, and subject consistency.”
The naming gets confusing, so here’s the product line: the original Nano Banana was Gemini 2.5 Flash Image (August 2025) — now the old version; Nano Banana Pro is Gemini 3 Pro Image (November 2025), slow but precise; Nano Banana 2 is Gemini 3.1 Flash Image (February 2026), the default for most of the past year; a cheaper Lite joined in June. Nano Banana 2.1 is the newest generation, live October 6.
The new model is already rolling out across the Gemini App, Search’s AI Mode, Flow, and the Gemini API. Google Search VP Robby Stein posted on X: open the Google App, tap the banana icon under the search box, and you’re in.
What Changed
Resolution: 1K, 2K, and 4K output tiers. The old 0.5K tier is gone.
Multi-image blending: up to 14 reference images per request, character consistency for up to 4 characters, object fidelity for up to 10 objects.
Editing: mask editing, multi-round character consistency, and text rendering all improved.
One small limitation: Google Cloud docs list seed, temperature, topP, topK, and logprobs as unsupported generation parameters — setting them errors out directly.
Pricing: per benchlm.ai’s compiled Gemini API public pricing, $0.0336 per 1K image, $0.0504 per 2K, $0.0756 per 4K, half price for batch calls. Generating 100 2K images costs $5.04 on the new model versus $10.10 on the previous generation and $13.40 on Pro. Note that input and thinking-token unit prices run higher than last gen — the total bill isn’t just the image line.
What Developers Must Do
Gemini 3.1 Flash Image shuts down on October 29. Code using the old model ID must switch to gemini-nano-banana-2.1 before then, or calls will fail. Test before migrating: drop unsupported parameters, and check prompt behavior against your own workflows.