GPT Image 2.5 vs Nano Banana Pro

Verified against OpenAI documentation on 2026-09-09

Two flagship image models shipped months apart, and they bill in completely different units. GPT Image 2.5 charges per token and Nano Banana Pro charges a flat rate per finished image. This page compares what both vendors have published, and is explicit about the head-to-head output tests we have not finished yet.

The two models

GPT Image 2.5 is OpenAI’s image model, released on 8 September 2026. It ships as two API models. `gpt-image-2.5-flare` is the default and handles everyday generation. `gpt-image-2.5-sunburst` trades speed for editing precision. Both cost the same per token, so the choice is about latency and control rather than budget.

Nano Banana Pro is Google’s model, published in the Gemini API as `gemini-3-pro-image`. Google positions it for work that is heavy on text and layout, naming infographics and mockups specifically. There is one model rather than a fast and a precise variant.

Both vendors are aiming at the same jobs. Both talk about rendering legible text, holding a subject steady across a set, and producing something a designer can hand over rather than a picture that merely looks plausible at thumbnail size.

What each vendor publishes

GPT Image 2.5Nano Banana Pro
VendorOpenAIGoogle
API model IDsgpt-image-2.5-flare, gpt-image-2.5-sunburstgemini-3-pro-image
Released8 September 2026Available in the Gemini API
Billing unitTokensFlat rate per image
Image output rate$30 per 1M tokens$120 per 1M tokens
Text input$5 per 1M tokens$2 per 1M tokens
Image input$8 per 1M tokens$2 per 1M tokens
Quality settingslow, medium, high, xhigh, max, autoNot exposed
Stated resolution ceilingNot published as a single figure4K, up to 4096 by 4096

OpenAI figures from the GPT-Image-2.5 model pages. Google figures from the Gemini API pricing page. Both read on 9 September 2026.

Price per image

OutputGPT Image 2.5 (via fal.ai)Nano Banana Pro
1K, low quality$0.00402$0.134
1K, medium quality$0.00903$0.134
1K, high quality$0.03612$0.134
1K, xhigh quality$0.06420$0.134
1K, max quality$0.14445$0.134
4K, high quality$0.10008$0.240
4K, max quality$0.40026$0.240

Google publishes a per-image price directly. OpenAI publishes token rates only, so the GPT Image 2.5 column uses fal.ai’s per-image figures for Sunburst, read on 9 September 2026. Longer prompts push the OpenAI numbers up.

Reading that table

The crossover sits around max quality at 1K. Below it GPT Image 2.5 is cheaper by an order of magnitude. A medium 1K image costs about a hundredth of what Nano Banana Pro charges for the same frame. For iteration, that difference decides the matter on its own.

Above the crossover the picture inverts. A max-quality 4K image from GPT Image 2.5 costs roughly $0.40 against Google’s $0.24. If every image you ship is a large finished piece, Google is cheaper and, more usefully, predictable. One rate, one number, no dependence on how long your prompt ran.

That predictability is worth something on its own. Token billing means the same request can cost different amounts as your prompts grow, and a team writing long structured prompts will drift upward without noticing. A flat per-image rate is easier to put in a budget.

One caveat on the OpenAI column. Those per-image figures come from fal.ai rather than OpenAI, because OpenAI publishes token rates and not a price list. Calling the API directly, your cost depends on your own prompt length and on how much world knowledge the request pulls in.

Where the feature sets differ

GPT Image 2.5 exposes six quality settings, from low through max. That is a real lever. It lets you draft at a hundredth of the finishing cost and only pay the full rate on the frame you keep. Nano Banana Pro does not expose an equivalent dial, so a draft and a final cost the same.

GPT Image 2.5 also splits generation and precision across two models. Flare returns images up to 50 percent faster than the previous generation, which matters when someone is sitting in front of the screen waiting. Sunburst takes longer and holds detail through repeated edits. Nano Banana Pro asks you to accept one speed.

Google states a resolution ceiling plainly at 4096 by 4096 and prices it separately. OpenAI does not publish a single ceiling figure, which makes planning a large-format workflow harder to do from the documentation alone.

On the consumer side, the ChatGPT app picked up several editing features alongside 2.5: sketching a rough layout as a reference, prebuilt templates for formats like posters, comments pinned to a spot on the image, and version history per edit. Those are product features rather than API features, so they do not affect an integration.

How to choose today

Pick GPT Image 2.5 if your workflow iterates. The quality dial and the token pricing reward throwing away drafts, and Flare is fast enough that a person will keep clicking. It also suits anyone already holding an OpenAI key who does not want a second vendor relationship.

Pick Nano Banana Pro if you ship finished large images and want one number in the budget. The flat rate removes prompt length from the cost equation, and the published 4K ceiling makes large-format planning straightforward.

Running both is a defensible answer for a production system. The request shapes are different, but the job is the same, and a second provider is the cheapest insurance against a rate limit at the wrong moment.

Frequently asked questions

Which one is cheaper?

It depends on the size and quality you ship. Below max quality at 1K, GPT Image 2.5 is dramatically cheaper, often by a factor of ten or more. At 4K and max quality, Nano Banana Pro is cheaper at $0.24 against roughly $0.40. The crossover falls near max quality at 1K.

Why does OpenAI not publish a price per image?

OpenAI bills images by token, at $30 per million output tokens, and the token count varies with size, quality and prompt length. Google bills a flat rate per finished image, so it can publish $0.134 and $0.24 directly. The per-image figures in the table above come from fal.ai, not from OpenAI.

Which renders text more reliably?

We have not run a controlled comparison, so we are not going to claim one. Both vendors describe text rendering as a focus. When our own runs are finished, the outputs and the prompts that produced them will be published on this page rather than summarised as a verdict.

Can I use both from images25?

Not in the first release. images25 runs GPT Image 2.5 only, on both Flare and Sunburst. Adding a second vendor means a second set of request shapes and a second pricing model, and we would rather ship one model properly first.

Is Nano Banana Pro the same as Nano Banana 2?

No. Nano Banana Pro is the higher-fidelity model and is published as gemini-3-pro-image in the Gemini API. Google positions it for text-heavy work such as infographics and mockups. Check the model ID before comparing prices, because the names are close enough to mix up.

What about MAI-Image-2.5?

That is a Microsoft model and has nothing to do with either of these. It shares a version number with GPT Image 2.5, which puts it in the same search results and causes real confusion. If you are comparing benchmarks or prices, check the vendor name first.

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