Comfy-Org/ComfyUI · error · ValueError

Invalid size for sora-2 model, only 720x1280 and 1280x720 ar

Error message

Invalid size for sora-2 model, only 720x1280 and 1280x720 are supported.

What it means

Raised by the Sora-2 node when model is "sora-2" and the size parameter is not one of the two supported resolutions (720x1280 portrait or 1280x720 landscape). Other models in the node skip this check. It fires before any request is sent to the OpenAI proxy endpoint.

Source

Thrown at comfy_api_nodes/nodes_sora.py:127

                    ($isProSize ? 0.5 : 0.1);
                  {"type":"usd","usd": $round($perSec * $dur, 2)}
                )
                """,
            ),
        )

    @classmethod
    async def execute(
        cls,
        model: str,
        prompt: str,
        size: str = "1280x720",
        duration: int = 8,
        seed: int = 0,
        image: Optional[torch.Tensor] = None,
    ):
        if model == "sora-2" and size not in ("720x1280", "1280x720"):
            raise ValueError("Invalid size for sora-2 model, only 720x1280 and 1280x720 are supported.")
        files_input = None
        if image is not None:
            if get_number_of_images(image) != 1:
                raise ValueError("Currently only one input image is supported.")
            files_input = {"input_reference": ("image.png", tensor_to_bytesio(image), "image/png")}
        initial_response = await sync_op(
            cls,
            endpoint=ApiEndpoint(path="/proxy/openai/v1/videos", method="POST"),
            data=Sora2GenerationRequest(
                model=model,
                prompt=prompt,
                seconds=str(duration),
                size=size,
            ),
            files=files_input,
            response_model=Sora2GenerationResponse,
            content_type="multipart/form-data",
        )

View on GitHub (pinned to 1c6d8d45b3)

Solutions

Set size to exactly "720x1280" or "1280x720"
Pick the orientation matching your content: 720x1280 for vertical, 1280x720 for horizontal

Example fix

# before
generate(model="sora-2", size="1920x1080", ...)

# after
generate(model="sora-2", size="1280x720", ...)

Defensive patterns

Strategy: validation

Validate before calling

SORA2_SIZES = {"720x1280", "1280x720"}
if model == "sora-2":
    assert size in SORA2_SIZES, f"sora-2 size must be one of {SORA2_SIZES}, got {size!r}"

Type guard

def is_valid_sora2_size(model: str, size: str) -> bool:
    return model != "sora-2" or size in ("720x1280", "1280x720")

Try / catch

try:
    await sora_execute(model="sora-2", size=size, ...)
except ValueError as e:
    if "Invalid size" in str(e):
        await sora_execute(model="sora-2", size="1280x720", ...)
    else:
        raise

Prevention

Hard-code the two allowed sora-2 sizes in workflow templates
Choose orientation from your input image's aspect ratio before calling

When it happens

Trigger: Calling the Sora node with model="sora-2" and size set to anything else (e.g. "1920x1080", "1024x1024", or a typo like "1280x720 ").

Common situations: Copying size settings from other video nodes that accept arbitrary resolutions; assuming sora-2 supports square or 1080p output; string formatting mistakes (extra spaces, uppercase X).

Related errors

AI-assisted analysis of Comfy-Org/ComfyUI@1c6d8d45b3 (2026-08-14). Data as JSON: /api/errors/c6de88df4be19d21. Report an issue: GitHub.