By Harry | Published: November 15, 2026
In the Imagen 4 vs Nano Banana Pro decision, the biggest difference is status: Google has shut down Imagen 4 on its own APIs, while Nano Banana Pro (Gemini 3 Pro Image) is generally available. Imagen 4 was a cheaper, prompt-only text-to-image model. Nano Banana Pro costs more per image but adds editing, reference images, 4K output, and search grounding.
So this comparison is really for two groups: teams moving old Imagen 4 workflows onto something supported, and anyone trying to understand what they gain and lose by moving. Below, you’ll see how the two models differ on design, editing, text, resolution, price, and watermarking, plus which current Google model fits each type of user.
Key Takeaways
- Imagen 4 was shut down in the Gemini API on August 17, 2026. Google Cloud’s model page listed June 30, 2026 as its retirement date on the enterprise platform.
- Imagen 4 cost $0.02 to $0.06 per image. Nano Banana Pro costs $0.134 per 1K or 2K image and $0.24 at 4K, or half that in batch mode.
- Imagen 4’s generate models didn’t support editing. Nano Banana Pro edits conversationally and accepts up to 14 reference images.
- Google’s own replacement for Imagen 4 in the Gemini API is Nano Banana 2.1, not Pro, which matters if cost drove your original choice.
- Both models embed SynthID watermarks, so switching doesn’t change your AI disclosure position.
The Status Check Most Comparisons Skip
Many Imagen 4 vs Nano Banana Pro pages were written when both models were live. That’s no longer true, and it changes the whole question. Here’s the timeline from Google’s official pages:
| Date | Event |
|---|---|
| August 14 to 15, 2025 | Imagen 4 family (Fast, Standard, Ultra) becomes generally available |
| November 20, 2025 | Nano Banana Pro launches in preview |
| February 17, 2026 | Imagen 4 preview model IDs shut down in the Gemini API |
| May 28, 2026 | Nano Banana Pro (gemini-3-pro-image) becomes generally available |
| June 15, 2026 | Google announces Imagen 4 deprecation in the Gemini API |
| June 30, 2026 | Retirement date listed on Google Cloud’s Imagen 4 model page |
| August 17, 2026 | Imagen 4 Fast, Standard, and Ultra shut down in the Gemini API |
Sources: the Gemini API deprecations page, the Gemini API release notes, and Google Cloud’s Imagen 4 model page. Google’s current image generation docs now describe Imagen as its “legacy text-to-image models (shut down).”
If you see Imagen 4 offered on a third-party platform, confirm with that provider how it’s served. Google’s own endpoints no longer list it as available.
Imagen 4 vs Nano Banana Pro at a Glance
| Criteria | Imagen 4 (Fast / Standard / Ultra) | Nano Banana Pro (Gemini 3 Pro Image) |
|---|---|---|
| Model type | Dedicated text-to-image model | Gemini-native image model built on Gemini 3 Pro |
| Inputs | Text prompt | Text plus up to 14 images |
| Editing | Not supported on generate models | Conversational, multi-turn editing |
| Max resolution | Up to 2K (Standard, Ultra); Fast up to 1408 x 768 | 1K, 2K, 4K |
| Aspect ratios | 5 | 14 |
| Images per request | Up to 4 | Limited by 32,768 output tokens |
| Search grounding | No | Yes |
| API price per image | $0.02 / $0.04 / $0.06 | $0.134 (1K/2K), $0.24 (4K) |
| Watermark | SynthID | SynthID; C2PA listed as supported |
| Status (Nov 2026) | Shut down on Google’s APIs | Generally available |
The table hides one important point. These models weren’t built to do the same job, so the price gap isn’t a straight markup.
Two Different Kinds of Image Model
Imagen is Google’s dedicated text-to-image line. Google’s Imagen 3 technical report describes that model as “a latent diffusion model that generates high quality images from text prompts.” Google hasn’t published a matching architecture paper for Imagen 4, but it called the family its “most advanced text-to-image model” in the August 2025 GA announcement.
In practice, a model like this takes a prompt and renders an image. It doesn’t hold a conversation, read your reference photos, or look anything up.
Nano Banana Pro works differently. It’s a Gemini model that outputs images, so it reasons about the request first. According to Google’s image generation docs, Gemini 3 image models always run a thinking step in the API, can produce up to two interim draft images, and bill those thinking tokens. That’s why it can follow multi-part instructions and pull real data from Google Search. It’s also why each image costs more and takes longer.
Think of it like this: Imagen 4 was a renderer, while Nano Banana Pro is closer to a designer who can also render.
Editing: Where the Gap Is Widest
Google Cloud’s Imagen 4 page lists customization, inpainting, object insertion and removal, outpainting, upscaling, and negative prompts as not supported on the Imagen 4 generate models. If you wanted a change, you rewrote the prompt and generated again. (Google did sell Imagen 4 upscaling separately on its cloud pricing page.)
Nano Banana Pro is built for editing. You can upload a photo and ask for a different background, swap a product color, or fix one detail over several turns. Google’s docs say it accepts up to 6 object images, 5 character images, and 3 style references, within a 14-image cap. That’s what makes it useful for brand work where the same product or person has to appear across many images.
Say you run a three-person agency making ad variants for a coffee brand. With Imagen 4, every new variant was a fresh roll of the dice. With Pro, you can upload the actual bag and logo and keep them consistent. If you’ve ever fought this problem with seeds, our explainer on making slight image variations shows why regenerating rarely gives you small, controlled changes.
Text Rendering: Both Claims Come From Google
Both models were marketed on better text. Google said Imagen 4 brought “substantial improvements in text rendering over our previous models.” For Nano Banana Pro, Google’s developer announcement says it produces clear, accurate text and can translate text on signs, menus, and packaging while keeping the layout.
We haven’t run controlled tests on either model, and Google didn’t publish a head-to-head text benchmark between the two. So we won’t call a winner here. What you can say from the documentation is that Pro adds abilities Imagen 4 never had: translating existing text in an uploaded image, and grounding infographics in search results. If your work is text-heavy, run your own sample set and check spelling closely either way.
Resolution and Aspect Ratios
Imagen 4 Standard and Ultra topped out at 2K, with sizes like 2048 x 2048 and 2816 x 1536. Imagen 4 Fast stayed at 1K-class sizes, up to 1408 x 768. All three supported five aspect ratios: 1:1, 3:4, 4:3, 9:16, and 16:9.
Nano Banana Pro supports 1K, 2K, and 4K, and Google Cloud’s model page lists 14 aspect ratios, including 21:9 and banner shapes like 4:1 and 8:1. One caveat for enterprise buyers: Google’s May 2026 GA announcement said 4K output was still in preview on its enterprise platform, while 1K and 2K were covered by the SLA.
For print or large displays, 4K is a real advantage. For social posts, 2K usually covers it.
API Pricing per Image
Google still prints Imagen 4 prices on its pricing pages, even though the models are shut down. Here are the official numbers as of November 2026:
| Model | Standard price per image | Batch price per image |
|---|---|---|
| Imagen 4 Fast | $0.02 | Not listed |
| Imagen 4 Standard | $0.04 | Not listed |
| Imagen 4 Ultra | $0.06 | Not listed |
| Nano Banana Pro, 1K or 2K | $0.134 | $0.067 |
| Nano Banana Pro, 4K | $0.24 | $0.12 |
| Nano Banana 2.1, 1K (for reference) | About $0.034 | Listed, check availability |
Sources: Gemini API pricing and Google Cloud generative AI pricing. Nano Banana Pro also bills input at $2.00 per 1M tokens (about $0.0011 per reference image) and thinking output at $12.00 per 1M tokens.
Here’s what that means at volume. A team generating 1,000 images a month paid $40 on Imagen 4 Standard. The same count at 2K on Nano Banana Pro costs $134 at standard rates, or $67 in batch. Moving straight from Imagen 4 Fast to Pro, the output bill goes from $20 to $134, more than six times higher.
That’s the main reason Google points Imagen users to Nano Banana 2.1 instead. Its 1K price sits between Imagen 4 Fast and Standard. If price is the deciding factor, our AI image generator comparison covers non-Google options too.
Availability Today
Nano Banana Pro is available through the Gemini API, Google AI Studio, and Gemini Enterprise Agent Platform (the Google Cloud service formerly called Vertex AI). In the Gemini app, Google’s limits page lists “Redo images with Nano Banana Pro” for Google AI Plus, Pro, and Ultra plans. There’s no free API tier.
Imagen 4 isn’t available for new work on any of those Google surfaces. The Gemini API lists gemini-nano-banana-2.1 as its replacement. Google Cloud’s Imagen 4 page named gemini-2.5-flash-image (the original Nano Banana) instead, but that model is now legacy, and Google’s docs recommend newer models for new projects.
SynthID and Content Credentials
Google says every Imagen 4 image carried an invisible SynthID watermark, and every image created or edited with Nano Banana Pro carries one too. Google Cloud’s model pages list C2PA Content Credentials, an industry metadata standard that records how an image was made, for both.
In the Gemini app, Nano Banana Pro images can also carry a visible sparkle watermark. At launch, Google said free and Google AI Pro users get it, while Ultra subscribers and AI Studio users don’t. For compliance purposes, moving from Imagen 4 to Pro doesn’t change much: both mark images as AI-made.
Pros and Cons
Imagen 4
- Pro: low, flat per-image prices ($0.02 to $0.06) made budgeting simple.
- Pro: up to four images per request, useful for quick option sets.
- Con: shut down on Google’s APIs, so it can’t anchor any new project.
- Con: no editing or reference images on the generate models.
- Con: capped at 2K and five aspect ratios.
Nano Banana Pro
- Pro: conversational editing with up to 14 reference images keeps products and people consistent.
- Pro: 4K output and 14 aspect ratios cover print and banner formats.
- Pro: search grounding helps with data-driven visuals like charts and infographics.
- Con: $0.134 per 2K image is several times Imagen 4’s old rates.
- Con: thinking can’t be disabled in the API, which adds cost and latency to every call.
Which Should You Pick? Imagen 4 vs Nano Banana Pro by User Type
Since Imagen 4 is gone from Google’s platforms, the real choice is which current model replaces it.
You used Imagen 4 Fast for high-volume, simple images. Don’t jump to Pro. Start with Nano Banana 2.1, Google’s named replacement, or Nano Banana 2 Lite if 1K output is enough. Pro would multiply your bill.
You used Imagen 4 Ultra for hero images. Pro is the natural step up. You get 4K, editing, and references. In batch mode, a 2K Pro image ($0.067) costs only slightly more than an Ultra image did ($0.06).
You make brand or product content. Pro’s reference images and multi-turn edits solve the consistency problem Imagen 4 never could. Our guide to AI image fusion explains the multi-image techniques involved.
You build infographics or text-heavy graphics. Test Pro first, since it’s the only one of the two with search grounding and in-image translation. Verify every number it draws.
You’re open to tools outside Google. Compare broadly before committing. Our Nano Banana Pro vs FLUX.2 breakdown covers a strong non-Google rival.
Our recommendation: move Imagen 4 workloads to Nano Banana 2.1 by default, then route only the images that need editing, 4K, or exact text to Nano Banana Pro. That split keeps most of your volume close to old Imagen 4 prices.
FAQ
Can I still use Imagen 4 in the Gemini API?
No. Google shut down Imagen 4 Fast, Standard, and Ultra in the Gemini API on August 17, 2026, after announcing the deprecation on June 15. Requests to those model IDs won’t return images. Google’s deprecations page lists gemini-nano-banana-2.1 as the replacement for all three.
Is Nano Banana Pro the official replacement for Imagen 4?
Not in Google’s docs. The Gemini API names Nano Banana 2.1 as Imagen 4’s replacement, and Google Cloud’s Imagen 4 page named the original Nano Banana. Pro is Google’s premium option for complex work, so pick it only when you need its extra editing, resolution, or accuracy.
Will my Imagen 4 prompts work in Nano Banana Pro?
Mostly, but not unchanged. Pro reads prompts as instructions to a reasoning model, so plain descriptive prompts still work, while Imagen-specific parameters such as image count don’t carry over. Also, the API call format differs because Pro uses the Gemini generate content interface rather than Imagen’s predict endpoint.
Is Nano Banana Pro slower than Imagen 4 was?
Google says Pro has higher latency than Gemini 2.5 Flash Image, and its thinking step can’t be turned off in the API. Google didn’t publish a direct speed comparison against Imagen 4. If speed matters most, test Nano Banana 2.1 or 2 Lite, which Google positions as its faster image models.
Do Imagen 4 and Nano Banana Pro images need AI labels?
Both embed SynthID, so they can be identified as Google AI images whatever you do. Labeling rules depend on the platform you publish on and where you operate. Check each ad network’s or social platform’s own policy, since some require disclosure for realistic AI imagery. This isn’t legal advice.
Harry covers artificial intelligence for AI Journal Now.
