Google and OpenAI shipped their latest image models within weeks of each other, and on Domer they now sit one row apart in the generator. Nano Banana 2.1 is Google's newest, GPT Image 2.5 arrived as a two-flavor pair (Flare for speed, Sunburst for detail). People ask which one to default to, and the honest answer depends on what you are making and what you pay per image.
Here is the configuration-level comparison, with the actual credit numbers from our image generator, not marketing rounding.
The short answer
Nano Banana 2.1 wins on price and aspect ratio range: a 1K image costs 6 credits against Flare's 10, and it ships unusual formats like 4:1 and 8:1 banners that GPT Image 2.5 does not offer. GPT Image 2.5 wins when you need many reference images in one edit (up to 16 against Nano Banana's 10) or want the Sunburst variant for slower, denser detail work. For everyday generation, start with Nano Banana 2.1 and reach for GPT Image 2.5 when the task is reference-heavy.
Price per image, for real
Both models price by resolution tier.
| Resolution | Nano Banana 2.1 | GPT Image 2.5 Flare | GPT Image 2.5 Sunburst |
|---|---|---|---|
| 1K | 6 credits | 10 credits | 10 credits |
| 2K | 10 credits | 16 credits | 16 credits |
| 4K | 15 credits | 25 credits | 25 credits |
Nano Banana 2.1 is roughly 40 percent cheaper at every tier. On a 2,400-credit pack that difference compounds: about 400 images at 1K versus 240. If you iterate heavily, and everyone does, the cheaper model buys more attempts.
Both are standard-tier models, so free-plan users can generate with them at the base resolution. Only the 4K tier sits behind paid access.
Aspect ratios and odd formats
Nano Banana 2.1 supports fourteen ratios, including 4:1, 1:4, 8:1, and 1:8. Those ultra-wide and ultra-tall formats matter more than they sound: web banners, sidebar creatives, and vertical story headers all live at ratios that most models simply refuse to produce, and cropping a 16:9 image to 8:1 destroys the composition.
GPT Image 2.5 covers the conventional twelve, from 1:1 through 21:9 and 9:8. Anything you would print or post fits. Anything shaped like a skyscraper does not.
Editing and reference images
This is where GPT Image 2.5 takes the lead. The image-to-image mode accepts up to 16 reference images per edit, the highest limit in our catalog. Face consistency across a multi-character scene, brand assets pulled from a dozen files, style blending from a big mood board: the 16-image window keeps more context in play.
Nano Banana 2.1 accepts 10 references through the same editor, which covers most single-subject work comfortably. Both models edit through the same flow: upload sources, describe the change, generate. No masks or brush selections on either.
One practical difference: GPT Image 2.5 comes in two flavors. Flare is the fast default. Sunburst costs the same credits but renders slower and denser, and it is the better pick for intricate textures or packed scenes. Nano Banana 2.1 has a single mode, which keeps decisions simple.
Text rendering
Both models render readable text, which was not true of image generators even a year ago. Short strings, headlines, and labels come out clean on both at 2K and above.
Where they differ is density. A poster with five lines of copy, a tagline, and a logo lockup stresses the layout, and this is where results get subjective fast. Our suggestion: run the same prompt on both at 2K, look at the kerning, and let your eyes vote. Typography quality shifts prompt by prompt more than model by model.
If typography is the whole job, though, check Ideogram 4.5, which is purpose-built for it and prices at 20 credits at its default quality.
Which one for which task
- Volume iteration, banners, odd aspect formats: Nano Banana 2.1
- Multi-reference edits, brand consistency, big context: GPT Image 2.5 Flare
- Slow, dense, detail-critical renders: GPT Image 2.5 Sunburst
- Cheapest 4K output: Nano Banana 2.1 at 15 credits
- Free-plan testing at 1K: either, both are standard tier
And for a third opinion, FLUX 3 Klein also landed this month with 4K at 12 credits and a 10-reference editor, sitting between the two on price.
FAQ
Is Nano Banana 2.1 better than GPT Image 2.5?
Neither is strictly better. Nano Banana 2.1 is cheaper per image and supports extreme aspect ratios. GPT Image 2.5 handles more reference images per edit and offers the slower Sunburst mode for dense detail. Pick per task, not per brand.
How much do they cost on Domer?
Nano Banana 2.1 costs 6, 10, and 15 credits at 1K, 2K, and 4K. GPT Image 2.5 Flare and Sunburst both cost 10, 16, and 25. Credits come from plans or pay-as-you-go packs.
Can free users generate with these models?
Yes. Both are standard-tier, so free accounts can generate at base resolutions. The 4K tier requires paid access on both models.
Which model is better at text in images?
Both render short text reliably at 2K and above. For typography-heavy work like posters and logos, Ideogram 4.5 is the stronger specialist. For everything else, test your actual prompt on both; results vary more by prompt than by model.
How many reference images does each accept?
GPT Image 2.5 accepts up to 16 reference images per edit. Nano Banana 2.1 accepts up to 10. Both edit through the same upload-and-describe flow in the image-to-image generator.
