Nano Banana 2 introduced as Gemini 3.1 Flash Image Preview

Google announced Nano Banana 2 on February 18, 2026 and exposed the API billing entry as Gemini 3.1 Flash Image Preview. Official Gemini API pricing lists $0.30 per 1M text/image/video input tokens, $1.00 per 1M audio input tokens, $2.50 per 1M output tokens, and $0.039 per generated image.