Seedream 5.5
seedream / 5-5-layer-decomposition

Seedream 5.5 is ByteDance Seed's image creation model, released on November 9, 2026. It keeps unedited regions intact across up to 100 rounds of editing, generates images with transparent backgrounds natively, and renders more realistic textures and dense small text.

Model Type:
Pricing: Layer decomposition is billed per output image, with each layer—including the base image—counted as one image: 3.6 credits per image ($0.018) at 1K / 1.5K, 6.3 credits per image ($0.0315) at 2K. The input image is billed separately at 1.44 credits ($0.0072) — 10% below official pricing. Example: 4 output images at 1K cost 1.44 + 4 × 3.6 = 15.84 credits ($0.0792). High-tier top-ups come with bonus credits that lower the effective price by about 10%.
Input

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.

0/2000

Click 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.

There is no guarantee that everything can be filtered out; if you are not satisfied with the results, you will need to make your own arrangements.
Output
output typeimage
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Generated output
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Examples

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

Seedream 5.5 runs on Kie.ai as three models through one API: text to image, image to image and layer decomposition. It edits the same image round after round without color shifts in unedited areas and returns transparent PNGs on request.
Seedream 5.5 API for Stable Multi-Turn Image Editing

What's New in Seedream 5.5

Seedream 5.5 is a multimodal image generation model built for precise, repeatable edits. The cards below cover its main upgrades and the separate layer decomposition model on Kie.ai.
Stable Multi-Turn Editing
01

Stable Multi-Turn Editing

Seedream 5.5 preserves unedited regions at the pixel level, removes color shifts in those areas and reduces detail loss across successive edits, so you can keep working on the same image for up to 100 rounds of editing.
Precise Changes to Small Details
02

Precise Changes to Small Details

Small items such as rings and eyeglass frames stay editable with precision even after a long run of successive edits, and a moved object keeps its perspective and occlusion coherent with the rest of the scene.
Native Transparent Backgrounds
03

Native Transparent Backgrounds

Seedream 5.5 generates images with an alpha channel, including full and partial transparency. On Kie.ai, set background to transparent with output_format png; in our test, a 2K request returned a 2048×2048 PNG with an alpha channel.
Reusable Characters and Styled Text Assets
04

Reusable Characters and Styled Text Assets

Characters can be reused as references across scenes while keeping their defining features and textures, and a reference image's brushwork, colors and materials can be applied to chosen text to produce transparent text assets.
More Realistic Lighting, Materials and Skin
05

More Realistic Lighting, Materials and Skin

Lighting, materials and skin textures look more natural, with less excessive gloss and overexposure and fewer blotchy textures in some images.
Clearer Written Characters and Small Text
06

Clearer Written Characters and Small Text

Seedream 5.5 renders complex character shapes and densely arranged small text more accurately, from newspaper-style pages to infographics.
Layer Decomposition Into Editable Layers
07

Layer Decomposition Into Editable Layers

The seedream/5-5-layer-decomposition model splits one image into a base image plus layers, up to 100 outputs in total (default 30), and returns each layer's z_index, bounding box, name and description. An optional prompt can point at an element with a tag, and text_recognition can be switched on to recognize text in the layers.
MeasureByteDance's own evaluation
Use cases testedE-commerce, marketing, film and television, gaming, office productivity, fashion design
Quality scores and usability ratesImproved across all six use cases versus Seedream 5.0 Pro
Usability rates in film and television and office productivityMore than twice those of Seedream 5.0 Pro
Pairwise preference (GSB) versus the previous versionPositive in all four comparisons, reaching +55.62% for realism in image-to-image tasks
Severe text corruption rateFell to 0.4%
Minor text corruption rateFell to 1.7%
ParameterSeedream 5.5 on Kie.ai
Modelsseedream/5-5-text-to-image, seedream/5-5-image-to-image, seedream/5-5-layer-decomposition
EndpointPOST https://api.kie.ai/api/v1/jobs/createTask
promptText to image and image to image: required, 5 to 5,000 characters; layer decomposition: optional, up to 2,000 characters, with tags to mark elements
aspect_ratioRequired. 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
size1K, 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_formatpng (default) or jpeg; in layer decomposition it applies to the base image only, and the separated layers are always PNG
backgroundText to image and image to image: auto (default), transparent or opaque; transparent output needs png
image_urlsImage 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_urlThe one image to split in layer decomposition: JPEG, PNG or WEBP, up to 10 MB
max_imagesLayer decomposition: 2 to 100 outputs (default 30), one base image plus layers; billing counts the images actually returned
text_recognitionLayer decomposition: optional, off by default; recognizes text in the layers
Output images per request1 for text to image and image to image

How to Use the Seedream 5.5 API on Kie.ai

Seedream 5.5 runs as an asynchronous task on the Kie.ai unified task API.
  1. 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. 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. 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. 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.

What You Can Build With Seedream 5.5

Iterative Image Editing Tools

Let your users refine one image step by step, changing a product, an accessory or an object's position, while unedited regions stay intact and detail holds up across edits.

Design Assets With Transparent Backgrounds

Create standalone design assets with full or partial transparency that can be used without separate background removal or edge cleanup; on Kie.ai, request them with background set to transparent and PNG output.

E-Commerce and Marketing Visuals

Produce product and campaign visuals with natural lighting and material textures.

Text-Heavy Layouts

Generate posters, infographics and other visuals with complex character shapes and densely arranged small text; the evaluation table on this page shows the text corruption rates.

Seedream 5.5 on Kie.ai

01

Three Seedream 5.5 Models, One Endpoint

Text to image, image to image and layer decomposition each have their own model name and all run on the same createTask endpoint, so one integration covers generation, editing and layering.
02

Seedream 5.0 Flash and Pro Are Here Too

Seedream 5.0 Flash and Seedream 5.0 Pro are also available on Kie.ai with the same key, so you can compare versions on your own prompts.
03

One Key Across the Kie.ai Market

All models in the Kie.ai market use the same authentication method: an Authorization: Bearer YOUR_API_KEY header with the key from your Kie.ai API Key Management page. Your account has one credit balance that all generation services draw from, and you can check it with the Get Remaining Credits API.
04

Nothing to Host

Kie.ai provides its models as an API; there are no GPUs or model weights to manage.

Frequently Asked Questions

What are the main features of Seedream 5.5?

Seedream 5.5 brings consistent multi-turn editing that preserves unedited regions, native generation of images with transparent backgrounds, more natural lighting, materials and skin textures, and more accurate rendering of complex characters and dense small text.

Can I keep editing the same image over many rounds?

Yes. Seedream 5.5 supports continued editing of the same image over many rounds, keeping unedited regions intact at the pixel level, removing color shifts in those areas and reducing detail loss.

Can Seedream 5.5 create images with transparent backgrounds?

Yes. On Kie.ai, set background to transparent and output_format to png in a text-to-image or image-to-image request. In our test, a 2K request returned a 2048×2048 PNG with an alpha channel. JPEG output cannot be transparent.

Can I use reference images with Seedream 5.5?

Yes. Use the seedream/5-5-image-to-image model and pass 1 to 10 reference images in image_urls together with a prompt and an aspect_ratio, which also accepts auto. Each input image is billed separately, and characters can be reused as references across scenes.

What is layer decomposition in Seedream 5.5?

It is a separate model, seedream/5-5-layer-decomposition, that splits one image into a base image and separate PNG layers. Each layer comes back with its stacking order, bounding box, name and description; you cap the number of outputs with max_images and can switch on text_recognition.

How does Seedream 5.5 compare with Seedream 5.0 Pro?

The comparison table on this page shows the evaluation results against Seedream 5.0 Pro across six use cases, from e-commerce to fashion design, including quality, usability and text corruption figures.

What aspect ratios and sizes does the Seedream 5.5 API support?

Both text to image and image to image require an aspect_ratio; image to image also accepts auto. Both take a size of 1K, 1.5K or 2K, with 2K as the default, and layer decomposition also accepts auto for size. The parameter table on this page lists every option.

How do I send my first Seedream 5.5 API request?

Get your API key, then POST to the createTask endpoint with the model seedream/5-5-text-to-image, a prompt and an aspect_ratio. Use the returned taskId with Get Task Details, or pass a callBackUrl. The steps on this page show the request settings and how to retrieve your result.

How much does the Seedream 5.5 API cost?

Seedream 5.5 is billed per output image by size, and input images are charged as well. Layer decomposition is billed for every image it returns, and size auto is billed at the 2K rate. Current rates are in the pricing card on this page. Your account has one credit balance that all generation services draw from; check it with the Get Remaining Credits API.