
Prompts for image generation
0/5000Width-height ratio of the image, determining its visual form.
Resolution tier of the output image. Affects the credit cost.
Output image format.
Background of the output image. "transparent" is not available when the output format is JPEG.
A configurable parameter. Defaults to true in the Playground.

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Click to upload or drag and drop
Supported formats: JPEG, PNG, WEBP Maximum file size: 10MB; Maximum files: 10
Input images (1–10). JPEG / PNG / WEBP, up to 10 MB each. Each input image is billed separately.
Prompts for image generation
0/5000Width-height ratio of the image, determining its visual form.
Resolution tier of the output image. Affects the credit cost.
Output image format.
Background of the output image. "transparent" is not available when the output format is JPEG.
A configurable parameter. Defaults to true in the Playground.

Explore different use cases and parameter configurations
Optional. Describe the elements to separate; leave empty to detect them automatically. Use <bbox>x1 y1 x2 y2</bbox> (0–1000 normalized) to mark positions.
0/2000Click to upload or drag and drop
Supported formats: JPEG, PNG, WEBP Maximum file size: 10MB
The image to decompose. JPEG / PNG / WEBP, up to 10 MB.
Resolution tier. "auto" keeps the input size (clamped to 1K–2K) and is billed at the 2K rate.
Format of the base image. Separated layers are always PNG.
Maximum number of output images, including the base image. Billed by the number actually returned.
Whether to recognize text in the layers.
A configurable parameter. Defaults to true in the Playground.





Explore different use cases and parameter configurations
README
Complete guide to using Seedream 5.5
Seedream 5.5 API for Stable Multi-Turn Image Editing

What's New in Seedream 5.5


Precise Changes to Small Details

Native Transparent Backgrounds

Reusable Characters and Styled Text Assets

More Realistic Lighting, Materials and Skin

Clearer Written Characters and Small Text

Layer Decomposition Into Editable Layers
Seedream 5.5 Compared With Seedream 5.0 Pro
Results from ByteDance's own evaluation on its MagicArena platform, scored by experienced evaluators across six use cases.
| Measure | ByteDance's own evaluation |
|---|---|
| Use cases tested | E-commerce, marketing, film and television, gaming, office productivity, fashion design |
| Quality scores and usability rates | Improved across all six use cases versus Seedream 5.0 Pro |
| Usability rates in film and television and office productivity | More than twice those of Seedream 5.0 Pro |
| Pairwise preference (GSB) versus the previous version | Positive in all four comparisons, reaching +55.62% for realism in image-to-image tasks |
| Severe text corruption rate | Fell to 0.4% |
| Minor text corruption rate | Fell to 1.7% |
Seedream 5.5 API Parameters on Kie.ai
Request parameters for the three Seedream 5.5 models on Kie.ai, as listed in the Kie.ai API docs.
| Parameter | Seedream 5.5 on Kie.ai |
|---|---|
| Models | seedream/5-5-text-to-image, seedream/5-5-image-to-image, seedream/5-5-layer-decomposition |
| Endpoint | POST https://api.kie.ai/api/v1/jobs/createTask |
| prompt | Text to image and image to image: required, 5 to 5,000 characters; layer decomposition: optional, up to 2,000 characters, with |
| aspect_ratio | Required. Text to image: 1:1, 4:3, 3:4, 16:9, 9:16, 2:3, 3:2 or 21:9; image to image: the same values plus auto |
| size | 1K, 1.5K or 2K (default 2K); layer decomposition also accepts auto (default), which keeps the input size within 1K to 2K and is billed at the 2K rate |
| output_format | png (default) or jpeg; in layer decomposition it applies to the base image only, and the separated layers are always PNG |
| background | Text to image and image to image: auto (default), transparent or opaque; transparent output needs png |
| image_urls | Image to image: required, 1 to 10 publicly accessible image URLs; JPEG, PNG or WEBP, up to 10 MB each; each input image is billed separately |
| image_url | The one image to split in layer decomposition: JPEG, PNG or WEBP, up to 10 MB |
| max_images | Layer decomposition: 2 to 100 outputs (default 30), one base image plus layers; billing counts the images actually returned |
| text_recognition | Layer decomposition: optional, off by default; recognizes text in the layers |
| Output images per request | 1 for text to image and image to image |
How to Use the Seedream 5.5 API on Kie.ai
- 1
Step 1: Try It in the Playground
Open the playground on this page, choose text to image, image to image or layer decomposition, and check results before you write any code. - 2
Step 2: Get Your API Key
Create an API key on your Kie.ai API Key Management page and include it in every request as Authorization: Bearer YOUR_API_KEY. - 3
Step 3: Send Your First Request
Send a POST request to https://api.kie.ai/api/v1/jobs/createTask with model set to "seedream/5-5-text-to-image". In the input object, provide your prompt and set aspect_ratio to "1:1", size to "2K", output_format to "png" and background to "transparent". The response returns a taskId. - 4
Step 4: Collect the Result
Check the task with the Get Task Details endpoint using its taskId, or pass a callBackUrl to be notified when it finishes, then download the image.