Seedream 5.5 · Image to Image

Create an image from a prompt and one or more reference images with Seedream 5.5. Submit an asynchronous generation request and retrieve the result from the task status endpoint or a webhook.

Developer API pricing

Provider: SeeAPI

USD estimate: $0.0037 / credit · Estimated equivalent, not an additional charge.

1K / 1.5K: 4.9 credits/gen (≈ $0.018/gen)

2K: 8.5 credits/gen (≈ $0.032/gen)

Add-on

Additional reference images: +2 credits/image (≈ $0.007/image) (billed per additional image)

Request

POST/v1/generations

AuthorizationSend your API key in the Authorization header using the Bearer scheme.Authorization: Bearer ****************

Header Params

stringrequired

A new, stable key for each generation request. Reuse it only when retrying the same request body.

max length: 255

Example:: seedream55-i2i-example-001

Body Params

application/json

stringrequired

The model ID shown in the selected model's API documentation.

Allowed:seedream-5-5

Default:: seedream-5-5
Example:: seedream-5-5

stringrequired

Image to Image. Use the Endpoint ID shown in this model's API documentation.

Allowed:image-to-image

Default:: image-to-image
Example:: image-to-image

stringoptional

Optional public Provider ID. Omit it to use the Endpoint default Provider (seeapi).

Allowed:seeapi

Default:: seeapi
Example:: seeapi

objectrequired

Model input validated against the selected Provider form_schema and api_policy.

The input object contains the prompt, reference images, and optional image-generation controls for this endpoint.

Provider parameters

SeeAPIseeapiDefault Provider

stringrequired

Text describing the requested image or transformation.

Required. Use 5–5000 characters to describe the requested edit or transformation.

min length: 5max length: 5000

Example:: Turn the reference image into a cinematic poster with warm evening light

array <uri>required

Reference images used to guide the generated image.

Required. Provide 1–10 image URLs.
Each image must be JPEG, PNG, or WebP and no larger than 10 MB.

min: 1max: 10min items: 1max items: 10

Example:: ["https://client.example.com/assets/reference.png"]

stringoptional

Controls the output aspect ratio.

Select the width-to-height ratio of the generated output.

Allowed:auto1:14:33:416:99:162:33:221:9

Default:: auto
Example:: auto

stringoptional

Selects the output resolution tier.

Optional. Defaults to `2K`. Allowed values are `1K`, `1.5K`, and `2K`.

Allowed:1K1.5K2K

Default:: 2K
Example:: 2K

stringoptional

Controls background handling.

Transparent is not available for JPEG

Allowed:autotransparentopaque

Default:: auto
Example:: auto

stringoptional

Selects the output image format.

Optional. Defaults to `png`. Use `png` when `background` is `transparent`.

Allowed:pngjpeg

Default:: png
Example:: png

booleanoptional

Enables the content safety check for this request.

Optional. Defaults to `false`.

Default:: false
Example:: false

string <uri>optional

An absolute HTTPS URL that receives the terminal generation Webhook.

max length: 2048

Example:: https://client.example.com/webhooks/seeapi

Responses

202The generation request was accepted and is still processing. Use the task status endpoint or the configured webhook to follow it.

Bodyapplication/json

The response includes the task identifier and credit accounting fields. The final image is available from the task status result after completion.

objectrequired

The asynchronous generation envelope returned by SeeAPI.

stringrequired

Use this identifier to query the task status endpoint.

Example:: task_xxx

stringrequired

The model ID used for the generation.

Example:: seedream-5-5

stringrequired

The Endpoint ID used for the generation.

Example:: image-to-image

stringrequired

The public Provider ID used for the generation.

Allowed:seeapi

seeapi: SeeAPI

Example:: seeapi

stringrequired

Current task state. The initial response is `processing`; query until a terminal state is returned.

Allowed:processing

Example:: processing

numberrequired

Estimated public credits for the request.

Example:: 10.5

numberrequired

Public credits consumed by the task.

Example:: 0

numberrequired

Public credits returned after a refundable failure or adjustment.

Example:: 0

string <date-time>required

Timestamp when the generation was created.

Example:: 2026-08-18T10:00:00Z

string <date-time>required

Timestamp of the latest task update.

Example:: 2026-08-18T10:00:00Z

booleanrequired

Whether the response replays an earlier request with the same idempotency key.

Example:: false

200The same idempotent request returned the existing generation.

Bodyapplication/json

The existing generation is returned without creating a second task or charging a second request.

objectrequired

The asynchronous generation envelope returned by SeeAPI.

stringrequired

Use this identifier to query the task status endpoint.

Example:: task_xxx

stringrequired

The model ID used for the generation.

Example:: seedream-5-5

stringrequired

The Endpoint ID used for the generation.

Example:: image-to-image

stringrequired

The public Provider ID used for the generation.

Allowed:seeapi

seeapi: SeeAPI

Example:: seeapi

stringrequired

Current task state. The initial response is `processing`; query until a terminal state is returned.

Allowed:processing

Example:: processing

numberrequired

Estimated public credits for the request.

Example:: 10.5

numberrequired

Public credits consumed by the task.

Example:: 0

numberrequired

Public credits returned after a refundable failure or adjustment.

Example:: 0

string <date-time>required

Timestamp when the generation was created.

Example:: 2026-08-18T10:00:00Z

string <date-time>required

Timestamp of the latest task update.

Example:: 2026-08-18T10:00:00Z

booleanrequired

Whether the response replays an earlier request with the same idempotency key.

Example:: false

400

Invalid JSON, parameters, Schema, or API Policy

401

Invalid API Key or authentication failed

402

Insufficient credits

403

The current request is not allowed

404

Model, Endpoint, or task not found

409

Idempotency conflict or the same request is still being created

413

Request body is too large

429

Too many requests

503

Service temporarily unavailable

Query Task Status

After submitting a task, use the unified query endpoint to check progress and retrieve results:

Get Task DetailsLearn how to query task status and retrieve generation results

For production workloads, provide `callback_url` and use the task status endpoint as a fallback when the webhook is delayed.

Related Resources

Market Overview

Explore all available models

Credits & Billing

View credit balance, plans, and billing activity

Usage

Review API usage and credit consumption

Callbacks

Manage the secret used to verify generation webhook signatures. Callback URLs are supplied when you create each generation.

Webhook flow

Callback URL per generation.

Webhook signing key

Code Examples

Request

const response = await fetch("https://api.seeapi.com/v1/generations", {
  method: "POST",
  headers: {
    "Authorization": "Bearer YOUR_API_KEY",
    "Idempotency-Key": "seedream55-i2i-example-001",
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
  "model": "seedream-5-5",
  "endpoint": "image-to-image",
  "provider": "seeapi",
  "input": {
    "prompt": "Turn the reference image into a cinematic poster with warm evening light",
    "input_images": [
      "https://client.example.com/assets/reference.png"
    ],
    "aspect_ratio": "auto",
    "resolution": "2K",
    "background": "auto",
    "output_format": "png",
    "nsfw_checker": false
  },
  "callback_url": "https://client.example.com/webhooks/seeapi"
})
});

const result = await response.json();

ResponseHTTP 202

{
  "generation": {
    "id": "task_xxx",
    "model": "seedream-5-5",
    "endpoint": "image-to-image",
    "provider": "seeapi",
    "status": "processing",
    "estimated_credits": 10.5,
    "consumed_credits": 0,
    "refunded_credits": 0,
    "created_at": "2026-08-18T10:00:00Z",
    "updated_at": "2026-08-18T10:00:00Z"
  },
  "idempotent": false
}

const response = await fetch("https://api.seeapi.com/v1/generations", { method: "POST", headers: { "Authorization": "Bearer YOUR_API_KEY", "Idempotency-Key": "seedream55-i2i-example-001", "Content-Type": "application/json" }, body: JSON.stringify({ "model": "seedream-5-5", "endpoint": "image-to-image", "provider": "seeapi", "input": { "prompt": "Turn the reference image into a cinematic poster with warm evening light", "input_images": [ "https://client.example.com/assets/reference.png" ], "aspect_ratio": "auto", "resolution": "2K", "background": "auto", "output_format": "png", "nsfw_checker": false }, "callback_url": "https://client.example.com/webhooks/seeapi" }) }); const result = await response.json();

{ "generation": { "id": "task_xxx", "model": "seedream-5-5", "endpoint": "image-to-image", "provider": "seeapi", "status": "processing", "estimated_credits": 10.5, "consumed_credits": 0, "refunded_credits": 0, "created_at": "2026-08-18T10:00:00Z", "updated_at": "2026-08-18T10:00:00Z" }, "idempotent": false }

Responses

202The generation request was accepted and is still processing. Use the task status endpoint or the configured webhook to follow it.

Bodyapplication/json

The response includes the task identifier and credit accounting fields. The final image is available from the task status result after completion.

objectrequired

The asynchronous generation envelope returned by SeeAPI.

stringrequired

Use this identifier to query the task status endpoint.

Example:: task_xxx

stringrequired

The model ID used for the generation.

Example:: seedream-5-5

stringrequired

The Endpoint ID used for the generation.

Example:: image-to-image

stringrequired

The public Provider ID used for the generation.

Allowed:seeapi

seeapi: SeeAPI

Example:: seeapi

stringrequired

Current task state. The initial response is `processing`; query until a terminal state is returned.

Allowed:processing

Example:: processing

numberrequired

Estimated public credits for the request.

Example:: 10.5

numberrequired

Public credits consumed by the task.

Example:: 0

numberrequired

Public credits returned after a refundable failure or adjustment.

Example:: 0

string <date-time>required

Timestamp when the generation was created.

Example:: 2026-08-18T10:00:00Z

string <date-time>required

Timestamp of the latest task update.

Example:: 2026-08-18T10:00:00Z

booleanrequired

Whether the response replays an earlier request with the same idempotency key.

Example:: false

200The same idempotent request returned the existing generation.

Bodyapplication/json

The existing generation is returned without creating a second task or charging a second request.

objectrequired

The asynchronous generation envelope returned by SeeAPI.

stringrequired

Use this identifier to query the task status endpoint.

Example:: task_xxx

stringrequired

The model ID used for the generation.

Example:: seedream-5-5

stringrequired

The Endpoint ID used for the generation.

Example:: image-to-image

stringrequired

The public Provider ID used for the generation.

Allowed:seeapi

seeapi: SeeAPI

Example:: seeapi

stringrequired

Current task state. The initial response is `processing`; query until a terminal state is returned.

Allowed:processing

Example:: processing

numberrequired

Estimated public credits for the request.

Example:: 10.5

numberrequired

Public credits consumed by the task.

Example:: 0

numberrequired

Public credits returned after a refundable failure or adjustment.

Example:: 0

string <date-time>required

Timestamp when the generation was created.

Example:: 2026-08-18T10:00:00Z

string <date-time>required

Timestamp of the latest task update.

Example:: 2026-08-18T10:00:00Z

booleanrequired

Whether the response replays an earlier request with the same idempotency key.

Example:: false

400

Invalid JSON, parameters, Schema, or API Policy

401

Invalid API Key or authentication failed

402

Insufficient credits

403

The current request is not allowed

404

Model, Endpoint, or task not found

409

Idempotency conflict or the same request is still being created

413

Request body is too large

429

Too many requests

503

Service temporarily unavailable