The official replacement is gemini-nano-banana-2.1. gemini-3.1-flash-image does not have a published shutdown date per Google Gemini API's deprecation page (checked 2026-10-17). Published on the official docs: input price $0.5 per million tokens, context window 131,072 tokens, max output 32,768 tokens.
gemini-3.1-flash-image model page · Google Gemini API
A migration diff is not published because the official page did not name a replacement model id.
The official replacement is gemini-nano-banana-2.1. gemini-3.1-flash-image does not have a published shutdown date per Google Gemini API's deprecation page (checked 2026-10-17). Published on the official docs: input price $0.5 per million tokens, context window 131,072 tokens, max output 32,768 tokens.
Price comparison is not published yet.
Context window sizes are not both published on the official pages we checked.