Prompting Google's Gemini Image Models
Google's image generation ships in tiers — all "Nano Banana" under the hood — and the first prompting decision is which tier, because it sets your cost/quality. Then the prompt craft is similar across them.
Pick the Tier First
- Nano Banana Pro (gemini-3-pro-image-preview) — ~94% text, grounding, 4K. Hero assets, text-heavy, factual images. See the Nano Banana prompting guide.
- Nano Banana 2 (gemini-3.1-flash-image-preview) — fast, strong quality, cheaper. Great default.
- Nano Banana Lite — cheapest, for high-volume/simple assets.
A Prompt Structure That Works
Order: subject → composition → style → text (quoted) → resolution.
Social ad for a coffee brand, top-down flat lay, warm tones,
minimalist style, headline text "MORNING FUEL" centered,
1:1, soft natural light, legible type
Craft Tips
- Quote text exactly and state placement — Gemini image models render quoted strings well, especially Pro.
- Describe composition (flat lay, rule-of-thirds, negative space) rather than just listing objects.
- Name the style ("flat vector", "photoreal", "watercolor").
- Set aspect ratio to your channel (1:1, 9:16, 16:9).
- Iterate with edits — provide the image and change one thing, instead of regenerating.
Generate
curl -X POST https://api.linkmodel.ai/api/v1/image-generation \
-H "Authorization: Bearer $LINKMODEL_API_KEY" -H "Content-Type: application/json" \
-d '{ "model": "gemini-3.1-flash-image-preview", "prompt": "<your structured prompt>", "size": "2K" }'Submit, get a task_id and price, poll for the image. Confirm parameters in the docs.
Cost-Smart Prompting
- Draft on Nano Banana 2 / Nano Banana Lite, finalize on Pro.
- Right-size resolution — 4K only for hero.
- Compare tiers and prices in cheapest image API; multilingual strengths in best multilingual AI image model.
Which Tier for Which Job
- Text/4K/factual → Nano Banana Pro.
- Everyday quality, cheaper → Nano Banana 2.
- High-volume/simple → Nano Banana Lite.
Bottom Line
Choose the Gemini image tier by cost/quality first, then prompt with clear composition and quoted text. Draft cheap and finalize on Pro to balance quality and spend — all on one key.
Start free with a $1 credit and test the tiers.