# Seedance 2.0 Fast API (ByteDance)

> Seedance 2.0 Fast is a speed-optimized Seedance 2.0 for 480p and 720p videos with audio — ideal for iteration and high-volume pipelines.

Page: https://cheapergen.com/models/bytedance/seedance-2.0-fast · API reference: https://cheapergen.com/models/bytedance/seedance-2.0-fast/api

## Pricing
Official list price source: BytePlus ModelArk official price ($5.6 / 1M tokens; $3.3 with video input). Prices verified 2026-10-14.

| Tier | Official | Cheaper Gen. | Save |
|---|---|---|---|
| 480p | $0.0562/s | $0.0438/s | 22% |
| 720p | $0.1210/s | $0.0942/s | 22% |

## Specs
- Resolutions: 480p · 720p
- Duration: 4–15 s
- Aspect ratios: 16:9 · 9:16 · 1:1 · 4:3 · 3:4 · 21:9
- Audio: Yes (included)

## Endpoints

### Text to Video — `POST https://cheapergen.com/api/v1/run/bytedance/seedance-2.0-fast/text-to-video`

| Param | Type | Required | Description |
|---|---|---|---|
| prompt | string | yes | Describe the shot: subject, action, camera movement, lighting and style. |
| aspect_ratio | string (enum) (16:9, 9:16, 1:1, 4:3, 3:4, 21:9) | no | Output frame shape. |
| resolution | string (enum) (480p, 720p) | no | Output resolution. Higher resolutions cost more per second. |
| duration | integer (4–15) | no | Length of the generated clip in seconds (4–15s). You pay per second. |
| generate_audio | boolean | no | Generate synchronized sound, ambience and dialogue. No extra cost. |
| seed | integer | no | Use the same seed and settings to reproduce a result. Leave empty for random. |

```bash
curl -X POST https://cheapergen.com/api/v1/run/bytedance/seedance-2.0-fast/text-to-video \
  -H "Authorization: Bearer $CHEAPERGEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "prompt": "A slow dolly-in on a ceramicist shaping a vase at golden hour, dust in the light, shallow depth of field",
  "aspect_ratio": "16:9",
  "resolution": "720p",
  "duration": 5
}'
```

### Image to Video — `POST https://cheapergen.com/api/v1/run/bytedance/seedance-2.0-fast/image-to-video`

| Param | Type | Required | Description |
|---|---|---|---|
| prompt | string | yes | Describe the shot: subject, action, camera movement, lighting and style. |
| image_url | string (URL) | yes | Image used as the opening frame. JPG/PNG/WebP, URL or upload. |
| end_image_url | string (URL) | no | Optional closing frame — the model animates between the two. |
| aspect_ratio | string (enum) (16:9, 9:16, 1:1, 4:3, 3:4, 21:9) | no | Output frame shape. |
| resolution | string (enum) (480p, 720p) | no | Output resolution. Higher resolutions cost more per second. |
| duration | integer (4–15) | no | Length of the generated clip in seconds (4–15s). You pay per second. |
| generate_audio | boolean | no | Generate synchronized sound, ambience and dialogue. No extra cost. |
| seed | integer | no | Use the same seed and settings to reproduce a result. Leave empty for random. |

```bash
curl -X POST https://cheapergen.com/api/v1/run/bytedance/seedance-2.0-fast/image-to-video \
  -H "Authorization: Bearer $CHEAPERGEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "prompt": "The camera pushes in as she turns and smiles; hair moves in the wind",
  "image_url": "https://cdn.cheapergen.ai/samples/portrait.jpg",
  "aspect_ratio": "16:9",
  "resolution": "720p",
  "duration": 5
}'
```

### Reference to Video — `POST https://cheapergen.com/api/v1/run/bytedance/seedance-2.0-fast/reference-to-video`

| Param | Type | Required | Description |
|---|---|---|---|
| prompt | string | yes | Describe the shot: subject, action, camera movement, lighting and style. |
| reference_image_urls | string[] (URLs) | no | Up to 9 images for characters, products, style or scene. Refer to them in the prompt as @Image1, @Image2… |
| reference_video_urls | string[] (video URLs) | no | Up to 3 MP4/MOV clips for motion, camera moves or effects (2–15 s each, 15 s in total, ≤ 50 MB in total). Refer to them as @Video1, @Video2… Reference-video seconds are billed together with the output, at the lower with-video token rate. |
| reference_audio_urls | string[] (audio URLs) | no | Up to 3 MP3/WAV clips for voice, music or sound (2–15 s each, 15 s in total, ≤ 15 MB each). Refer to them as @Audio1, @Audio2… Needs at least one reference image or video. |
| aspect_ratio | string (enum) (16:9, 9:16, 1:1, 4:3, 3:4, 21:9) | no | Output frame shape. |
| resolution | string (enum) (480p, 720p) | no | Output resolution. Higher resolutions cost more per second. |
| duration | integer (4–15) | no | Length of the generated clip in seconds (4–15s). You pay per second. |
| generate_audio | boolean | no | Generate synchronized sound, ambience and dialogue. No extra cost. |
| seed | integer | no | Use the same seed and settings to reproduce a result. Leave empty for random. |

```bash
curl -X POST https://cheapergen.com/api/v1/run/bytedance/seedance-2.0-fast/reference-to-video \
  -H "Authorization: Bearer $CHEAPERGEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "prompt": "@Image1 unboxes the product from @Image2 on a marble desk, copying the camera move of @Video1",
  "reference_image_urls": [
    "https://cdn.cheapergen.ai/samples/reference-1.jpg",
    "https://cdn.cheapergen.ai/samples/reference-2.jpg"
  ],
  "reference_video_urls": [
    "https://cdn.cheapergen.ai/samples/reference-1.mp4"
  ],
  "aspect_ratio": "16:9",
  "resolution": "720p",
  "duration": 5
}'
```

## Getting the result
Jobs are async. Poll `GET https://cheapergen.com/api/v1/generations/{id}` until status is succeeded/failed/canceled, or pass `webhook_url`. Failed generations are refunded automatically.

## FAQ
**How is Seedance 2.0 Fast priced?**
Seedance 2.0 Fast is billed by video tokens, exactly like ByteDance's official API: tokens = output seconds × width × height × 24 ÷ 1024. The tables above show the equivalent price per second at 16:9. With reference videos, the reference seconds are added to the output seconds and all of them are billed at a lower "with video input" rate. Audio is included at no extra cost and failed generations are never charged.

**Is this the official Seedance 2.0 Fast model?**
Yes. Requests run on ByteDance's Seedance 2.0 Fast through official API channels — the same weights and output quality, at a lower price.

**Can I use the output commercially?**
Yes, generated videos can be used commercially, subject to ByteDance's content policy and our Terms of Service. Do not upload content you do not have rights to.

**How long does a generation take?**
Typical 5-second clips finish in about one to three minutes depending on resolution and queue load. You can poll the task or receive a webhook when it completes.

Seedance 2.0 Fast is developed by ByteDance. Cheaper Gen. provides API access and does not own the model.