Short answer: choose GPT Image 2.5 when you need a transparent background, an exact pixel size, outpainting or the cheapest possible drafts; choose Nano Banana when you need the same character or product to stay consistent across many images, or an extreme 1:8 or 8:1 format. Both families are in the model list on Lunart, and you can switch between them on every generation.
Feature comparison
| GPT Image 2.5 | Nano Banana | |
|---|---|---|
| Versions | Flare, Sunburst | 2.1, 2, Pro, 2 Lite |
| Reference images | Up to 16 | Up to 14 (2.1, 2, Pro) |
| Resolution | 1K / 2K / 4K | 1K / 2K / 4K (2 adds 512; Lite is 1K only) |
| Custom pixel size | Yes, up to 3840 px per edge, ratio up to 3:1 | No |
| Aspect ratios | Presets plus custom | 14 on 2.1 and 2, including 1:4, 4:1, 1:8, 8:1; 10 on Pro and Lite |
| Transparent background | Yes | No (use Remove background afterward) |
| Outpainting | Yes | No |
| Quality levels | Auto, Low, Medium, High, X-High, Max | — |
| Thinking level | — | Fast, Balanced, Deep on 2.1 |
| Credits per image | 3 to 75 | 4 to 50 |
Within GPT Image 2.5, Flare is the fast generalist with strong text rendering, and Sunburst is tuned for faithful edits that keep faces, layout and text unchanged. Within Nano Banana, 2.1 is the everyday choice, Pro is for high-fidelity finals, and Lite is for quick 1K drafts.
Credit cost side by side
Credits per image at typical settings:
| Scenario | GPT Image 2.5 (Flare or Sunburst) | Nano Banana |
|---|---|---|
| Cheapest draft | 3 (Low, 1K) | 4 (2 Lite, 1K) |
| Everyday 1K | 5 (Medium) / 12 (High) | 8 (2.1) |
| 2K | 15 (Medium) / 22 (High) | 12 (2.1) / 30 (Pro) |
| 4K | 30 (Medium) / 37 (High) / 75 (Max) | 25 (2.1) / 50 (Pro) |
GPT Image 2.5 pricing is the quality level (3 to 50 credits) plus a resolution add-on (0 for 1K, 10 for 2K, 25 for 4K). Nano Banana is priced by resolution only. In practice, GPT Image 2.5 at Low or Medium is the cheapest way to explore, while Nano Banana 2.1 is the cheaper route to high-resolution output if you would otherwise run GPT Image 2.5 at High or above. The composer always shows the exact total before you generate, and failed generations are refunded automatically.
Which to pick, by use case
Logos, stickers, icons and product cutouts. GPT Image 2.5. Turn on Transparent background and you get a PNG with no background in one step, with no separate removal pass.
Marketplace and ad images at a fixed size. GPT Image 2.5. Enter the exact width and height your Amazon listing, Shopify theme or ad slot needs as a custom size.
A recurring character or mascot. Nano Banana. Keep one set of reference images and change only the pose and setting in the prompt. It holds facial features and outfits well across a series.
Editing a photo without changing the person. GPT Image 2.5 Sunburst is built for this: swap the background or fix a detail while the face, layout and text stay put. Nano Banana 2.1 also makes clean localized edits.
Posters with headlines and prices. GPT Image 2.5 Flare first. For a dense layout, run the same prompt on Nano Banana Pro and compare.
Website strip banners and long mobile graphics. Nano Banana 2.1 or 2, using 1:4, 4:1, 1:8 or 8:1.
Turning a portrait image into a wide banner. GPT Image 2.5, using Outpaint. Nano Banana does not outpaint.
A workflow that uses both
Many projects combine them on one canvas:
- Explore 4 to 6 directions with GPT Image 2.5 Flare at Low or Medium, 1K, or with Nano Banana 2 Lite.
- Use the strongest result as a reference image and produce the final with Nano Banana Pro or GPT Image 2.5 at High, 4K.
- Fix small details with Omni Edit, and use Remove background or Split layers if the image is going into a larger design.
Because every result stays on the infinite canvas, comparing versions is a matter of looking at them side by side.
Learn more
Both model families are available as soon as you sign up for Lunart.