zhenzhen-video-v31-lowprice

One node, three models, one duration

The v31 node is zhenzhen's consolidation of its Seedance V3.1 line: instead of separate Fast and Quality nodes (and later a Lite one), you get a single node with a model dropdown. That's the whole convenience - swap zhenzhen-video-v31-fast for zhenzhen-video-v31-quality without rebuilding anything, and know that zhenzhen-video-v31-lite exists when you want the cheapest fixed-8-second text-to-video run.

The catch is in the title: this model family is locked to 8 seconds. There's no seconds dropdown with choices - the schema literally offers only "8" - and the code validates it, throwing "Video V3.1 duration is fixed at 8 seconds" if you try anything else. If you need 30-second clips, that's the GK node's job. This is the middle-length, higher-quality seat.

How it works

Same shape as every node in the "Seedance2 Low Price" category: an HTTP client that uploads your reference images to zhenzhen's server, submits a task to the closed Seedance API, polls, downloads the MP4, and hands you a ComfyUI VIDEO. No local weights, no VRAM, just a credit balance and patience. V3.1 is one of those closed video models with no open weights, so an API wrapper is the only way it gets into a Comfy graph (external-api-nodes.md).

Inputs that matter

• model - fast, quality, or lite. Fast for drafts, quality for the keeper, lite for the cheapest throwaway.
• prompt - the description. English is the safe bet.
• resolution - 720p, 1080p, or 4k. The price lever.
• ratio - 16:9 or 9:16.
• image1…image3 - optional reference images for consistency. One real gotcha here: lite is text-to-video only. Connect an image to lite and the node refuses, "zhenzhen-video-v31-lite is text-to-video only and does not accept images." Fast and Quality accept the references.

api_config takes the shared Seedance 2.0 Low Price Settings node with your domestic-site key (or set SEEDANCE_API_KEY). The seed input is cache control only - the tooltip is explicit that it isn't sent to the API.

Outputs and install

The standard four: video, video_url, task_id (recovery handle for the site's async-task page), and response (JSON). Install is pack-wide:

cd ComfyUI/custom_nodes
git clone https://github.com/T8mars/Comfyui-zhenzhen

or ComfyUI Manager → search "Comfyui-zhenzhen", then restart and let requirements install. The README's universal advice for these nodes: a 500 means the provider is struggling - rerun once before you start changing settings.