AI ultrawide wallpaper and banner API: which Sume models list 21:9

If you want an ultrawide desktop wallpaper or a wide site banner from the Sume image API, 7 catalog rows list aspect_ratio: "21:9", read 2026-10-03: Nano Banana 2, Nano Banana Pro, Qwen Image, Qwen Image Max, Flux 2 Pro, Flux 2 Flex, Recraft V4. The cheapest is Qwen Image at $0.025 per image. For even wider shapes, Nano Banana 2 lists 4:1 and 8:1, and the two Ideogram rows list 3:1.

A model only accepts the values in its own descriptor, and a ratio outside it returns 400 unsupported_parameter. Because Sume does not take explicit pixel sizes on /v1/images, generate at the closest ratio and crop to your exact monitor or banner size afterwards.

Rows by wide ratio

A 21:9 request

Ask for compositions that survive a crop: a subject off-center with empty space on both sides, or a pattern with no focal point. A call that is still running after the 30-second wait returns 202 with a job envelope instead of 200, so check the status code before reading data; see Jobs and results.

import os
import requests

resp = requests.post(
    "https://api.sume.com/v1/images",
    headers={"Authorization": f"Bearer {os.environ['SUME_API_KEY']}"},
    json={
        "model": "black-forest-labs/flux.2-pro",
        "prompt": "misty pine forest ridge at sunrise, wide cinematic composition, no text",
        "aspect_ratio": "21:9",
    },
    timeout=60,
)
resp.raise_for_status()
if resp.status_code == 202:
    print("still running:", resp.json()["data"]["status_url"])
else:
    for image in resp.json()["data"]:
        print(image["url"])

Crop and resize

Fit the result to your target without stretching, and keep the original file. The same helper works for a banner or a wallpaper.

from PIL import Image, ImageOps

img = Image.open("wide.png")
ImageOps.fit(img, (3440, 1440), method=Image.LANCZOS).save("wallpaper-3440x1440.png")

Which row for what

• Cheapest wide still: Flux 2 Pro at $0.0375, up to 4 per call.
• Reference-guided wide edit: Nano Banana 2 or Pro, Qwen Image or either Flux row (all take references).
• Text-only, no references: Qwen Image Max and Recraft V4.
• Narrow strip with a title: Ideogram V3 or 4.5 at 3:1, then check the lettering yourself.