Seedance API: Text-to-Video and Image-to-Video

Seedance is ByteDance's video generation model — fast render times and a low cost per clip, which makes it a good default for teams generating video at volume rather than one-off hero shots. This guide covers calling it for text-to-video and image-to-video, and the async task/webhook flow you'll actually run in production.

Through the Aigenway gateway you get Seedance behind the same API key, task contract, and prepaid USD balance as every other model — no separate ByteDance account or credit pack.

What you get

Seedance ships a handful of tiers trading speed against fidelity. Codes and availability shift, so confirm what's live on your account before hardcoding a model string:

curl "https://api.aigenway.com/v1/methods?provider=seedance" \
  -H "Authorization: Bearer sk_live_..."

That call returns the exact model and method values to use below, plus per-tier pricing. Roughly, expect a fast/cheap tier for drafts and a higher-fidelity tier for final output — the same trade-off you see across Kling and Veo.

Text-to-video

Send a prompt, get back a task. Idempotency-Key makes retries safe — resend the same key and you get the same task back instead of paying twice.

curl -X POST https://api.aigenway.com/v1/generations \
  -H "Authorization: Bearer sk_live_..." \
  -H "Idempotency-Key: $(uuidgen)" \
  -H "Content-Type: application/json" \
  -d '{
    "provider": "seedance",
    "model": "seedance-1-pro",
    "method": "text_to_video",
    "params": {
      "prompt": "a paper airplane gliding through a sunlit office, slow motion, shallow depth of field",
      "duration": 5,
      "aspect_ratio": "16:9"
    }
  }'

Image-to-video

Animate a still you already control — a product shot, a character render, a frame from a previous generation. Pass the source image plus a motion prompt:

curl -X POST https://api.aigenway.com/v1/generations \
  -H "Authorization: Bearer sk_live_..." \
  -H "Idempotency-Key: $(uuidgen)" \
  -H "Content-Type: application/json" \
  -d '{
    "provider": "seedance",
    "model": "seedance-1-pro",
    "method": "image_to_video",
    "params": {
      "prompt": "camera slowly pulls back, product rotates gently",
      "input_image": "https://example.com/product-shot.png",
      "duration": 5
    }
  }'

Because the request shape is identical to text-to-video (same endpoint, same provider/model/method/params fields, just a different method and an added input_image), switching between the two is a one-line change in your integration.

The async task and webhook flow

Video is never synchronous — the POST above returns a task in queued or processing state immediately, not a finished clip. You have two ways to get the result:

1. Poll. GET /v1/generations/{task_id} until status moves to succeeded (or failed) and read the output URL off the response.
2. Webhook. Set a callback_url in the request and the gateway POSTs the finished task to your endpoint the moment it completes — no polling loop to run or rate-limit against.

curl -X POST https://api.aigenway.com/v1/generations \
  -H "Authorization: Bearer sk_live_..." \
  -H "Idempotency-Key: $(uuidgen)" \
  -H "Content-Type: application/json" \
  -d '{
    "provider": "seedance",
    "model": "seedance-1-pro",
    "method": "text_to_video",
    "params": { "prompt": "drone shot rising over a foggy pine forest at dawn", "duration": 5 },
    "callback_url": "https://your-app.example.com/webhooks/aigenway"
  }'

The task shape — fields, status values, webhook payload and signature — is identical across every model on the gateway. Code you write against Seedance keeps working unchanged if you add Kling or Veo later. Full details are in the task lifecycle and webhooks docs.

Why one gateway beats a ByteDance-only account

• One integration, many models. The same request shape that calls Seedance also calls Kling, Veo and every image model — swap a string, not your SDK.
• Real USD billing. Prepaid balance, no regional credit packs to buy and forecast; check spend from the API at any time.
• Production plumbing included. Idempotency keys, queueing, task state and signed webhooks are already built — you don't reimplement them per provider.

When ByteDance ships a new Seedance version, you point at the new model code from /v1/methods and keep shipping.