What it is
Nano Banana 2.1 (model ID gemini-nano-banana-2.1) became generally available on the Gemini API on 6 October 2026. It replaces Nano Banana 2 (gemini-3.1-flash-image), which Google has deprecated with no shutdown date announced, and Google positions it as the cheaper, faster counterpart to Nano Banana Pro. Google lists gains in visual quality, prompt following, text and infographic rendering, and character consistency across turns.
It outputs 1K, 2K and 4K images, combines up to 14 reference images (keeping up to 4 characters and 10 objects consistent), can ground images in Google Web and Image Search, and has minimal, medium and high thinking levels. Input is capped at 131,072 tokens. It is rolling out across the Gemini app, AI Mode in Search, AI Studio, Flow, Stitch, Google Ads and Gemini Enterprise.
Our review
Nano Banana 2.1 is the strongest image model you can buy for under five cents a picture. Artificial Analysis places it fourth on its text-to-image board with an Elo of 1176, behind only OpenAI's two GPT Image 2.5 settings and GPT Image 2, which each cost about $211 per 1,000 images against Nano Banana 2.1's $33.60. It also sits 58 points clear of Nano Banana Pro (1118), which costs four times as much at 1K.
Google's own evaluation puts it ahead of both Nano Banana 2 and Nano Banana Pro in every category it lists, with the largest jump in infographic accuracy (0.521 with thinking, against 0.179 for Nano Banana 2). Those are Google's numbers. The Decoder's reporters were less convinced: on a deliberately awkward prompt, Pro's image still had more natural colour and proportion, and 2.1 shrank a horse into something closer to a pony. Both findings can hold at once. Blind votes reward prompt fidelity and layout, while photoreal scale is where Pro still earns its price.
Read the price sheet closely. At launch The Decoder reported 4K at 7.56 cents; Google's pricing page now bills a 4K image as 3,780 output tokens, or $0.113, so high-resolution work costs more than early coverage suggested. Thinking tokens are billed separately at $7.50 per million, Search grounding costs $14 per 1,000 requests after 5,000 free a month, and there is no free API tier.
Engineers should also note what the model does not do: no function calling, structured outputs or context caching, so it sits behind an orchestrating text model rather than replacing one. On a new Google Cloud billing account, the Tier 1 cap of $250 works out to roughly 7,400 1K images before an automatic upgrade is needed.
Where it earns its place
An e-commerce team producing lifestyle shots for 5,000 SKUs
Put the same product into many scenes without reshoots
Pass product photos as reference images (up to 10 objects stay consistent) and run jobs through the Batch API: 5,000 2K images cost about $126 at batch rates. Check proportions by eye; The Decoder found the model can get relative sizes wrong.
A backend engineer adding image generation to a consumer app
Generate a 1K image per user request at low cost
Call gemini-nano-banana-2.1 with thinking at minimal to cut latency and thinking-token spend; 100,000 images a month is about $3,360 at standard rates. New billing accounts start at Tier 1 with a $250 cap, so plan the tier upgrade before launch.
A B2B content team making explainers and infographics
Produce charts and labelled diagrams with readable text
Turn on Search grounding and high thinking; Google's infographic-accuracy score rises from 0.328 without thinking to 0.521 with it. Grounding is free for 5,000 requests a month, then $14 per 1,000.
Before you commit
- Setup
- An API key from Google AI Studio and one generateContent call. The model is paid-tier only on the API, so a billing account must be linked first.
- Integrations
- Gemini API and SDKs, Batch API, AI Studio and Gemini Enterprise; also built into Flow, Stitch and Google Ads. No function calling, structured outputs or caching.
- Data and privacy
- On the paid API tier Google does not use prompts or images to improve its products, but keeps them for an unspecified period for abuse monitoring; grounded requests are stored for 30 days. Apps serving the EEA, UK or Switzerland must use paid services.
- Cost at scale
- 100,000 1K images a month is about $3,360 ($1,680 on Batch); the same volume at 4K is about $11,300. Add $1.50 per million input tokens for prompts and reference images, and thinking output at $7.50 per million.
- Limits
- 131,072 input and 32,768 output tokens. Per-model rate limits are shown only in AI Studio, not published; Tier 1 accounts have a $250 billing cap and a $10 spending limit per rolling 10 minutes.
What's good
- Fourth on Artificial Analysis's text-to-image board at $33.60 per 1,000 images
- Up to 14 reference images, with 4 characters and 10 objects kept consistent
- Batch API halves the price at every resolution
- Search grounding for infographics and current subjects
What's not
- 4K costs $0.113, more than three times the 1K price
- Nano Banana Pro still looks more natural on some prompts, per The Decoder
- No free API tier, function calling or caching
- Closed weights, Google only
Best for
Product and marketing teams generating thousands of images a month who need consistent characters or legible text.
Alternatives
Nano Banana 2.1: common questions
- Is Nano Banana 2.1 worth it?
- Fourth in blind votes at a sixth of the leaders' price, Nano Banana 2.1 is the image model every rival now has to justify its cost against. We rate it 4.6 out of 5.
- How much does Nano Banana 2.1 cost?
- Gemini API: about $0.034 per 1K image, $0.050 per 2K and $0.113 per 4K; Batch halves each. No free API tier; free to try in the Gemini app.
- What are the downsides of Nano Banana 2.1?
- 4K costs $0.113, more than three times the 1K price; nano Banana Pro still looks more natural on some prompts, per The Decoder; no free API tier, function calling or caching; closed weights, Google only.
- Who is Nano Banana 2.1 best for?
- Product and marketing teams generating thousands of images a month who need consistent characters or legible text.
- How much does Nano Banana 2.1 cost for a team or in production?
- 100,000 1K images a month is about $3,360 ($1,680 on Batch); the same volume at 4K is about $11,300. Add $1.50 per million input tokens for prompts and reference images, and thinking output at $7.50 per million.
- Is Nano Banana 2.1 safe for company data?
- On the paid API tier Google does not use prompts or images to improve its products, but keeps them for an unspecified period for abuse monitoring; grounded requests are stored for 30 days. Apps serving the EEA, UK or Switzerland must use paid services.
- What are the best Nano Banana 2.1 alternatives?
- The closest alternatives we have reviewed are GPT Image 2.5 (Flare and Sunburst), Nano Banana Pro (Gemini 3 Pro Image), MAI-Image-2.6 and Seedream 5.0 Pro.
Answers checked Oct 22, 2026.
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