KIE Seedance V1 Pro Fast (I2V) [SL]

The "Fast" in the name is the whole pitch. This is ByteDance's Seedance V1 Pro tuned for speed over the flagship's bells and whistles - one image in, a prompt, and a quick clip back. If Seedance 1.5 Pro is the quality node and Kling is the feature node, this one is the scout: cheap, fast, good enough to know whether a shot is worth a pricier render.

It's the most minimal Seedance here. No aspect-ratio picker, no audio flag, no multi-frame support - just resolution, duration, and go. That restraint is a feature for iteration. When you're running a batch of "animate these 12 keyframes" and half of them are going to be thrown away anyway, you don't want to be tuning camera knobs on each one. You want the fast lane.

The inputs that matter

• prompt - required, up to a very generous 10,000 characters.
• images - required, first image used (batch extras ignored). The single frame to animate.
• resolution - 720p or 1080p. Note this one goes to 1080p, where the 1.5 Pro node tops out at 720p.
• duration - 5 or 10 seconds.

Output is video in ComfyUI's VIDEO format; SaveVideo to keep the file, since the node returns a temporary reference.

How it works

Same KIE job pipeline as every node in this pack: upload the frame as PNG, create a task for bytedance/v1-pro-fast-image-to-video, poll until it renders, download the MP4, hand back a VIDEO object. Transient 429/5xx errors auto-retry with backoff. The model name and the "Fast" branding are KIE's; the mechanism is identical to its siblings.

Install

Standard for the pack:

cd ComfyUI/custom_nodes
git clone https://github.com/v3devv/ComfyUI-Kie-API-Serverless

or ComfyUI Manager → search "Kie-API-Serverless" → restart. No models to download, no extra dependencies, just a KIE key pasted into the node's api_key field.

Where people get burned

"Fast" means faster, not free - it's still a metered video call, and at 1080p/10s it's not dramatically cheaper than the flagship. The real risk is treating a draft pass as final: V1 Pro Fast is a scout, so if you've iterated a prompt to a keeper, spend the extra on 1.5 Pro (or Kling) for the deliverable. And remember the moderation reality of any closed ByteDance model - what Seedance refuses, no node setting changes. Batch your scouts at 720p/5s, promote the survivors.