NanoBananaPro Native Google Format Aspect Ratio Output

Generate images with specified aspect ratios and resolutions using Google's native format API

Overview

Nano Banana Pro (gemini-3-pro-image-preview) supports various aspect ratios and resolution options, allowing you to precisely control the dimensions of generated images.

Supported Aspect Ratios

Nano Banana Pro supports the following aspect ratios:

1:1 - Square images
16:9 - Standard landscape
9:16 - Standard portrait
4:3 - Traditional landscape
3:4 - Traditional portrait
3:2 - Camera standard (landscape)
2:3 - Camera standard (portrait)
21:9 - Ultra-wide
5:4 - Display ratio (landscape)
4:5 - Display ratio (portrait)

Supported Resolutions

Each aspect ratio supports three resolution levels:

1K Resolution (Quick Preview)

Aspect Ratio	Resolution
1:1	1024×1024
16:9	1376×768
9:16	768×1376
4:3	1200×896
3:4	896×1200
3:2	1232×816
2:3	816×1232
21:9	1584×672
5:4	1136×896
4:5	896×1136

2K Resolution (Recommended)

Aspect Ratio	Resolution
1:1	2048×2048
16:9	2752×1536
9:16	1536×2752
4:3	2400×1792
3:4	1792×2400
3:2	2464×1632
2:3	1632×2464
21:9	3168×1344
5:4	2272×1792
4:5	1792×2272

4K Resolution (Ultra HD)

Aspect Ratio	Resolution
1:1	4096×4096
16:9	5504×3072
9:16	3072×5504
4:3	4800×3584
3:4	3584×4800
3:2	4928×3264
2:3	3264×4928
21:9	6336×2688
5:4	4544×3584
4:5	3584×4544

API Request Format

Basic Request Structure

{
  "contents": [{
    "parts": [
      {"text": "Your image description"}
    ]
  }],
  "generationConfig": {
    "responseModalities": ["IMAGE"],
    "imageConfig": {
      "aspectRatio": "16:9",
      "image_size": "2K"
    }
  }
}

Parameter Description

responseModalities: Must be set to ["IMAGE"] to return an image
aspectRatio: Aspect ratio, choose from the supported ratios above
image_size: Resolution level, options are "1K", "2K", "4K"

Example Code

cURL Example

curl -X POST "https://api.ai.soraliststudio.com/v1beta/models/gemini-3-pro-image-preview:generateContent" \
  -H "Authorization: Bearer sk-YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "contents": [{
      "parts": [
        {"text": "A cute kitten sitting in a garden, oil painting style, high definition, rich in detail"}
      ]
    }],
    "generationConfig": {
      "responseModalities": ["IMAGE"],
      "imageConfig": {
        "aspectRatio": "16:9",
        "image_size": "2K"
      }
    }
  }'

Python Example

import requests
import base64

API_KEY = "sk-YOUR_API_KEY"
API_URL = "https://api.ai.soraliststudio.com/v1beta/models/gemini-3-pro-image-preview:generateContent"

payload = {
    "contents": [{
        "parts": [
            {"text": "A cute kitten sitting in a garden, oil painting style, high definition, rich in detail"}
        ]
    }],
    "generationConfig": {
        "responseModalities": ["IMAGE"],
        "imageConfig": {
            "aspectRatio": "16:9",
            "image_size": "2K"
        }
    }
}

headers = {
    "Authorization": f"Bearer {API_KEY}",
    "Content-Type": "application/json"
}

response = requests.post(API_URL, headers=headers, json=payload, timeout=600)

if response.status_code == 200:
    data = response.json()
    image_base64 = data["candidates"][0]["content"]["parts"][0]["inlineData"]["data"]
    
    # Save image
    with open("output.png", "wb") as f:
        f.write(base64.b64decode(image_base64))
    print("Image saved as output.png")

Performance Recommendations

Recommended Timeout Settings

Different resolutions require different processing times. Set appropriate timeout values:

1K Resolution: 360 seconds (6 minutes) - For quick previews
2K Resolution: 600 seconds (10 minutes) - Recommended for daily use
4K Resolution: 1200 seconds (20 minutes) - Ultra HD quality

Bandwidth Optimization

Since image data is transferred using base64 encoding, the data volume is large:

Recommended to use metered high-speed bandwidth
Avoid network congestion affecting upload and download speeds
4K image base64 data may exceed 10MB

Notes

Higher resolution means longer generation time: Choose the appropriate resolution based on your actual needs
Price impact: Different resolutions may have different prices, check the latest pricing
Network stability: High-resolution image transfers require a stable network connection
Reasonable timeout settings: Set sufficient timeout to avoid request interruption

NanoBananaPro Native Google Format Aspect Ratio Output

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