model guide
Nano Banana 2.1 Ext: Per-Image Priced AI Edits
Nano Banana 2.1 Ext guide with per-image pricing, 1K-4K output, reference editing, Kansova credit costs, and limitations.
TL;DR
The same Nano Banana 2.1 quality, billed per image instead of by token usage.
Who this is for
- Brands producing campaign assets at 2K or 4K.
- Designers who need faithful reference-guided edits.
- Teams comparing image models by cost per finished asset.
Best for / Not best for
Best for
- 1K-4K output
- Reference-guided edits
- Campaign assets
- Material and texture fidelity
Not best for
- Low-cost bulk drafts
- Exact logo reproduction
- Video generation
- CAD-accurate output
Parameters
| Parameter | Supported value | Notes |
|---|---|---|
| Model | nano-banana-2.1-ext | Ext version, billed per image by resolution tier. |
| Output size | 1K, 2K, or 4K | 4K doubles the credit cost. |
| Aspect ratio | 14 presets, 1:4 through 8:1 | Common ratios: 1:1, 16:9, 9:16, 4:3. |
| Reference image | Image-to-image supported | Output follows the reference aspect ratio when size is omitted. |
| Images per request | One | Ext upstream only accepts one image per request. |
Pricing
Kansova bills generations in credits. Basic is $9.90/month for 300 credits; Pro is $19/month for 750 credits; Studio is $39/month for 1,700 credits.
| Generation | Kansova credits | Cost methodology |
|---|---|---|
| 1K or 2K image | 8 credits | Per-image pricing by resolution tier |
| 4K image | 16 credits | Per-image pricing by resolution tier |
| Reference edit | Same as generation tier | No extra image charge upstream |
Comparison
| Dimension | Nano Banana 2.1 | Nano Banana 2.1 Ext | Nano Banana Pro | Nano Banana |
|---|---|---|---|---|
| Primary strength | Newest Gemini edits | Predictable pricing | 4K premium edits | Fast edits |
| Billing basis | Token usage | Per image | Per generation | Per generation |
| Max output | 4K | 4K | 4K | 4K |
| Kansova cost | 8-16 credits | 8-16 credits | 8-16 credits | 4-8 credits |
| Best workflow | Latest quality | Cost planning | Final 4K assets | Rapid variations |
Prompt examples
- 01
Premium glass serum bottle on a pale blue plinth, soft water caustics, clean ecommerce lighting, 1:1. - 02
Replace the chair in this interior with a low sculptural stone bench while preserving camera angle and lighting. - 03
Minimal editorial still life of brushed steel objects on dark glass, precise reflections, restrained luxury campaign. - 04
Modern concrete courtyard house at dusk, warm interior light, native planting, realistic architectural visualization. - 05
Create three colorway concepts for this packaging while preserving its proportions and label hierarchy.
Known limitations
- Ext upstream accepts only one image per request; Kansova generates one per task anyway.
- Logos and small typography still require manual review.
- Reference fidelity varies with edit complexity.
- Provider availability can change output tiers without notice.
Alternatives
Frequently asked questions
How many credits does Nano Banana 2.1 Ext use?
Kansova charges 8 credits for a 1K or 2K image and 16 credits for 4K.
Why choose Ext over the official version?
Ext is billed per image by resolution tier, so the cost for a given output size is predictable. The official version is billed upstream by token usage, which varies with prompt length and reference images.
Is the image quality different?
No. Both offer the same output dimensions and image quality.
Last updated
2026-11-10
Sources and methodology
Capabilities were checked against the provider API material supplied to Kansova and the live Kansova controls on 2026-07-06. Credit figures are taken from the production pricing function; provider rates are reference figures and may change independently.
- EvoLink API documentation index
Provider documentation used to verify image modes and output tiers.
- Kansova product facts
Canonical list of supported workflows and current limitations.
- Kansova pricing
Current subscription and monthly credit allowances.