SeeDream 5.5 - Unifically

Generate images using ByteDance SeeDream 5.5, released in November 2026. Supports text-to-image, image editing with up to 10 reference images, transparent-background output, 8 aspect ratios, and resolution tiers up to 2K. 1K and 1.5K share one price, 2K costs more, and each reference image adds a small charge. See the whole family: SeeDream API models.

Model

bytedance/seedream-5.5

Parameters

Parameter	Type	Required	Default	Description
`prompt`	string	Yes	—	Text prompt describing the desired image
`aspect_ratio`	string	No	`"1:1"`	`1:1`, `4:3`, `3:4`, `16:9`, `9:16`, `3:2`, `2:3`, `21:9`. Combined with `resolution` to pick the output pixel size (e.g. 2K + 16:9 → 2624x1472)
`image_urls`	string[]	No	`null`	Reference image URLs for image editing (max 10). Omit for text-to-image. Must be public `https` URLs
`resolution`	string	No	`"2K"`	`1K`, `1.5K`, `2K` (case-insensitive)
`output_format`	string	No	`"png"`	`jpeg`, `jpg`, `png`
`transparent_background`	boolean	No	`false`	Return the subject on a transparent background (PNG with an alpha channel). Requires `output_format` `png`
`nsfw_check`	boolean	No	`false`	Check the prompt and input images for NSFW content before generating. Off unless set to `true`

Example - Text-to-Image

curl -X POST https://api.unifically.com/v1/tasks \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "model": "bytedance/seedream-5.5",
    "input": {
      "prompt": "A ripe red apple on a wooden table, soft window light",
      "aspect_ratio": "16:9",
      "resolution": "2K"
    }
  }'

Example - Image-to-Image

curl -X POST https://api.unifically.com/v1/tasks \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "model": "bytedance/seedream-5.5",
    "input": {
      "prompt": "Turn this photo into a watercolor painting",
      "image_urls": [
        "https://example.com/photo.jpg"
      ],
      "resolution": "1K",
      "aspect_ratio": "4:3"
    }
  }'

Example - Transparent Background

curl -X POST https://api.unifically.com/v1/tasks   -H "Content-Type: application/json"   -H "Authorization: Bearer YOUR_API_KEY"   -d '{
    "model": "bytedance/seedream-5.5",
    "input": {
      "prompt": "A single red apple sticker, die-cut, isolated subject",
      "resolution": "1K",
      "transparent_background": true
    }
  }'

SeeDream 5.5 generates exactly one image per request. Unknown parameters are rejected, including the max_sequential_images and web_search parameters available on SeeDream 5.0 Lite. transparent_background cannot be combined with jpeg output.

Response

{
  "code": 200,
  "success": true,
  "data": {
    "task_id": "9aeaaa15-5a73-472e-9ac0-27beddaa63ba",
    "status": "processing"
  }
}

Volume discounts are available for almost all models. Reach out at contact@unifically.com to discuss custom pricing.

​Model

​Parameters

​Example - Text-to-Image

​Example - Image-to-Image

​Example - Transparent Background

​Response

Model

Parameters

Example - Text-to-Image

Example - Image-to-Image

Example - Transparent Background

Response