The official Nano Banana image API is a paid developer route for the current Nano Banana 2 and Nano Banana Pro preview models: as of April 20, 2026, Google's public pricing rows show no free tier for gemini-3.1-flash-image-preview or gemini-3-pro-image-preview.
That does not mean every Nano Banana surface is paid. Creating an API key, using consumer products, and receiving provider credits are separate contracts; none of them should be treated as a blanket free official API entitlement.
For most API workloads, start with Nano Banana 2 because it is the cheaper default. Move to Pro when text accuracy, diagrams, final 4K assets, or expensive rework makes the higher price worth it; evaluate gateway or provider offers only after the official Google price and ownership boundary is clear.
Start With The Contract Board
The useful answer is not one number. Nano Banana API pricing has four layers that must stay separate.
| Layer | What it answers | Current practical answer |
|---|---|---|
| Official developer API output | What Google charges for generated images through the Gemini API route | Paid for the current Nano Banana 2 and Pro preview image models |
| API key creation | Whether a developer can create credentials and a project | A key can be created, but that is not a free generation entitlement |
| Consumer or product surfaces | What happens in Gemini app, AI Mode, Flow, or similar product routes | Plan, credit, and product rules apply separately from API billing |
| Gateway or provider route | Whether another vendor offers credits, lower rates, or compatibility | Vendor-owned contract; useful only after the official baseline is clear |
This split is the reason a one-line "Nano Banana API is free" answer is unsafe. It hides the contract owner. A developer budgeting a product integration needs the Google price row. A consumer asking whether a product UI still has access needs the product-surface rule. A team comparing gateway offers needs the provider's terms, not a rewritten Google row.
The model names also need one clean mapping. Google's image-generation documentation maps Nano Banana 2 to gemini-3.1-flash-image-preview, Nano Banana Pro to gemini-3-pro-image-preview, and the older Nano Banana lane to gemini-2.5-flash-image. Use the reader-facing names when discussing the decision, but use the model IDs when you are setting up requests, logs, billing, or support tickets.
Official Price Rows Checked On April 20, 2026
The price table answers the official API question, not every free-access question. Google's Gemini API pricing page is the owner for these rows, so treat the numbers as date-bound and recheck them before procurement or a large run.
| Google model route | Standard price per image | Batch / Flex price per image | Free tier |
|---|---|---|---|
gemini-3.1-flash-image-preview at 0.5K | $0.045 | $0.022 | Not available |
gemini-3.1-flash-image-preview at 1K | $0.067 | $0.034 | Not available |
gemini-3.1-flash-image-preview at 2K | $0.101 | $0.050 | Not available |
gemini-3.1-flash-image-preview at 4K | $0.151 | $0.076 | Not available |
gemini-3-pro-image-preview at 1K / 2K | $0.134 | $0.067 | Not available |
gemini-3-pro-image-preview at 4K | $0.240 | $0.120 | Not available |
Two details matter more than the table length suggests.
First, Nano Banana 2 is cheaper at every overlapping size. It also has a 0.5K lane that Pro does not expose in the same way. That makes it the rational default for drafts, iterations, high-volume product jobs, and API workflows where the image is not a high-risk final asset.
Second, Batch / Flex is an official discount lane, not a gateway trick. If the job can wait, the official Google route can be much cheaper without leaving the Google contract. A queue of 1,000 Nano Banana 2 2K images is $101 on Standard pricing and $50 on Batch. A 1,000-image Nano Banana Pro 4K run is $240 on Standard and $120 on Batch / Flex. That is often the first cost lever to check before comparing outside providers.
For a deeper Pro-only breakdown, use the Nano Banana Pro pricing guide. For Nano Banana 2-only budgeting, use the Nano Banana 2 API pricing guide.
What "Free" Can And Cannot Mean
The free-access problem is usually not about whether the word "free" appears somewhere. It is about which surface the word belongs to.
| Claim | Safe interpretation | What not to infer |
|---|---|---|
| "I can create a Gemini API key" | You can set up credentials through Google AI Studio / Google Cloud project paths | The current image preview models have free generated output |
| "Gemini or Flow lets me try images" | A consumer or product surface may have plan, quota, or credit rules | The developer API has the same entitlement |
| "A provider offers free credits" | A vendor may fund or promote its own route | Google has made the official API free |
| "AI Studio shows a project or quota page" | Live quota belongs to the project/account state | Every model row has a free tier |
That distinction is not pedantic. It changes the next action. If the reader is building code, they need to know whether generated images are billed by Google's API route. If the reader is experimenting in Gemini or Flow, they need the consumer product's current limits. If the reader is evaluating a provider, they need to ask who owns the credits, billing, data handling, support, and recovery path.
Use the dedicated free API key reality guide when the question is credential setup versus paid output. Use the Nano Banana 2 online free guide when the real job is consumer access rather than developer API billing.
Nano Banana 2 vs Pro Is A Default-And-Override Rule
The model choice is not a neutral winner table. It is a routing rule: use Nano Banana 2 first, then pay for Pro when the failure mode justifies it.
| Workload | Start with | Why |
|---|---|---|
| Fast drafts, variants, product ideation, and high-volume API jobs | Nano Banana 2 | Lower official price, more size lanes, and a speed/efficiency profile |
| Everyday image generation where rework is acceptable | Nano Banana 2 | The cost of another iteration is usually lower than the cost of starting on Pro |
| Text-heavy social cards, labels, mockups, and diagrams | Nano Banana Pro | Text and structured visual fidelity are usually the expensive failure points |
| Final client-facing or high-stakes assets | Nano Banana Pro | The premium is easier to justify when the image must survive close inspection |
| Unsure which model to route by default | Nano Banana 2 first | Escalation is cheaper than making Pro the baseline by habit |
The important correction is that Pro is not the general baseline. It is the premium override. If a team makes Pro the default for every request, it pays the Pro premium even when the workload mostly needs lower-cost iteration. If a team refuses to use Pro at all, it can spend more time repairing text, diagrams, or final assets than it saved in image cost.
The cleaner implementation policy is to record why a request escalates. A rule like "Pro only for text-heavy, diagram-like, final-pass, or failed-Nano-Banana-2 jobs" is easier to debug than "use Pro when quality matters." The first rule can be logged and reviewed. The second rule becomes a vague preference.
For the full model comparison, including consumer-surface behavior, use Nano Banana 2 vs Nano Banana Pro.
Pick The Route After The Official Baseline Is Clear
Once the official price and model rule are clear, route choice becomes much easier.
Use Google direct when the workload needs first-party model identity, official pricing, direct quota ownership, Google project billing, or clean auditability. This is the right default for teams that care about governance, reproducibility, or support boundaries. The practical setup path lives in the Nano Banana API guide.
Use Batch / Flex when the workload is still Google-owned but latency is flexible. This is the official cheap lane for queued image generation, asset backlogs, scheduled production, or background jobs where a slower finish is acceptable.
Use a consumer surface when the work is not a developer integration. Gemini app, AI Mode, Flow, and similar product experiences have their own plan and credit rules. Those routes can be useful, but they should not be used to budget API output.
Use a gateway or provider route when the real blocker is integration friction, billing flow, regional access, compatibility, or multi-model routing. That can be a legitimate route, but it is not the same contract as Google's price page. Treat provider prices, credits, limits, uptime, and support as vendor-owned claims unless they have been verified for the exact route you plan to use.
The stable Nano Banana API route guide is the better follow-up when the question becomes Google direct versus a gateway versus dual-lane routing. This hub should only decide when that branch is relevant; it should not turn into a provider directory.
Practical Budget Examples
The price rows become easier to use when converted into workload decisions.
For draft-heavy work, start with Nano Banana 2 and use the lowest size that still serves the task. Fifty 1K Standard images cost $3.35. Fifty 2K Standard images cost $5.05. If the same batch can wait, Batch pricing brings those to $1.70 and $2.50. That is the kind of workload where Pro-first routing is hard to justify.
For final-asset work, the Pro premium may be rational. Ten Pro 4K Standard images cost $2.40, while ten Nano Banana 2 4K Standard images cost $1.51. The dollar gap is small at that scale; the real question is whether Pro reduces the risk of unusable text, layout, or diagram structure.
For high-volume production, latency decides a lot. A 10,000-image Nano Banana 2 2K Standard run is $1,010. Batch pricing is $500. A 10,000-image Pro 4K Standard run is $2,400, while Batch / Flex is $1,200. At that point, the first decision is often not "which provider is cheapest?" but "which jobs can leave the Standard lane?"
For provider comparison, do the math only after the official baseline is anchored. If a provider quotes a lower price, ask what model route, output size, safety behavior, retry policy, data handling, and support path the quote includes. A lower vendor number can be useful. It should not be allowed to rewrite the official Google number.
FAQ
Is the official Nano Banana image API free?
For the current Nano Banana 2 and Nano Banana Pro preview image models, Google's public pricing rows checked on April 20, 2026 show Free Tier: Not available. Creating an API key or using a consumer product surface does not change that developer API price row.
Is creating a Gemini API key free?
Credential creation and generated output are different things. You may be able to create credentials through Google AI Studio or a Google Cloud project, but the generated image output for the current preview image models is governed by the pricing rows above.
Is Nano Banana 2 cheaper than Nano Banana Pro?
Yes. Nano Banana 2 is cheaper at every overlapping official API size shown in the current Google price rows. That is why it should be the default for most API workloads.
When should I use Nano Banana Pro instead of Nano Banana 2?
Use Pro when text accuracy, diagrams, infographics, final asset quality, or expensive rework matters more than the extra price. Do not make Pro the baseline just because it sounds like the premium version.
Are provider credits or gateway prices the same as Google pricing?
No. Provider credits and gateway prices belong to the vendor route. They can be useful, but they are separate from Google's official price rows, quota ownership, support path, and project billing.
What should I check before a large API run?
Recheck Google's pricing page, confirm the model ID, choose Standard versus Batch / Flex, verify your project quota in AI Studio or Google Cloud, and decide whether any provider or gateway route is allowed to own part of the workload.