When was Seedream 5.5 released?

ByteDance announced Seedream 5.5 on November 9, 2026, in a post on its Seed blog. The announcement did not include an API release date, model ID or price.

Is there a Seedream 5.5 API?

Yes. On reAPI, send a request to POST /api/v1/images/generations with the model set to doubao-seedream-5-5, then poll the task for the image URL. The full parameter list is in the Seedream 5.5 API docs.

Where can I try Seedream 5.5 today?

Right on this page: the playground above runs Seedream 5.5 with the same parameters as the API. ByteDance's own apps, such as Dreamina, also offer it.

Is Seedream 5.5 free or paid?

Paid. Each output image is billed by size band (1K or 1.5K, or 2K), and each reference image adds a charge; see the pricing table on this page. $1 buys 1,000 credits, and technical or provider failures are refunded automatically.

Does Seedream 5.5 require a monthly subscription?

Not on reAPI. reAPI has no subscription for any model: you buy credits, they never expire, and you only spend them on generations you run.

How do I get a Seedream 5.5 API key?

Sign up and create a key in the dashboard. The same reAPI key works for Seedream 5.5 and every other model on your account; pass it as a Bearer token in the Authorization header.

Can Seedream 5.5 generate transparent backgrounds?

Yes. Set background to transparent with PNG output, from a text prompt or reference images, and Seedream 5.5 returns an image with an alpha channel. ByteDance shows feathers, claws and lettering kept clean without a separate background-removal step.

How many edits can Seedream 5.5 handle on one image?

ByteDance demonstrates 100 successive edits, each using the previous output as input, while unedited regions stay pixel-identical and colors do not drift. That is a vendor demo, not an independent benchmark.

Is Seedream 5.5 better than GPT Image 2.5 and Nano Banana 2.1?

In ByteDance's own expert comparisons, Seedream 5.5 led GPT Image 2.5 Sunburst and Nano Banana 2.1 on text structure for both text-to-image and image-to-image, and had a substantial edge in text-to-image realism. No independent benchmark has been published yet.

Will there be a Seedream 5.5 Pro?

Yes. ByteDance says a Pro version of the Seedream 5.5 series will follow, without giving a date.

Seedream 5.5 — Text & Image to Image Generation

Seedream 5.5 is ByteDance's newest Seedream image model: stable edits across 100 rounds, native transparent output and cleaner small text. Generate from a prompt or up to ten reference images and pay per image.

Highlights: Seedream 5.5 is ByteDance's newest Seedream model · 1K, 1.5K or 2K
Best for: Iterative edits, transparent assets, posters with small text
Input: Text, plus up to 10 reference images
Output: One image per request, or a base image plus layers

Input

Prompt

Optional for layer decomposition

Size

2K · 1.5K · 1K · auto · ratio · WIDTHxHEIGHT

Resolution

1K · 1.5K · 2K

Reference images

Drag images here or click to upload

0/10 files

Up to 10 · public URLs

Images

Always 1

Layer decomposition

needs exactly 1 reference image

Max images

2–100 · default 30

Text recognition

Layer decomposition only

Background

auto · opaque · transparent

Output format

png · jpeg

Prompt optimization

standard

Watermark

Off by default

Estimated cost~$0.02323 credits

Result

Try one of these prompts

Pricing

Credit-based — 1 credit = $0.001 USD. Pay only for completed generations.

First test cost

$0.01313 credits

One sample at the cheapest tier (1 image).

Testing budget guide

Add credits

$10

≈ 769 tests

$50

≈ 3846 tests

$100

≈ 7692 tests

Per image · 1K or 1.5K: $0.013; Price · 1 image
Per image · 2K: $0.023; Price · 1 image
Per image · 1K or 1.5K · with 1 reference image: $0.019; Price · 1 image
Per image · 2K · with 1 reference image: $0.028; Price · 1 image

What is Seedream 5.5?

Seedream 5.5 is the next-generation image creation model from ByteDance's Seed team, announced on November 9, 2026. ByteDance built it around three upgrades: multi-turn editing that preserves unedited regions at the pixel level, native RGBA output with full and partial transparency, and more realistic images with clearer text. In ByteDance's own evaluation across e-commerce, marketing, film and television, gaming, office and fashion design, Seedream 5.5 scored higher than Seedream 5.0 Pro on quality and usability in all six. On reAPI, Seedream 5.5 runs on the async images endpoint and is billed per output image plus each reference image.

What you can build with this model

Real-world workflows and production use cases you can build and ship with this model.

Seedream 5.5 multi-turn image editing with unedited regions preserved

Edit the same image 100 times

Small errors pile up as one output becomes the next input: colors shift and details wash out. Seedream 5.5 is trained to leave the parts you did not ask to change alone. ByteDance's demo runs 100 successive edits on one portrait and still lands a precise change on a ring or an eyeglass frame.

Seedream 5.5 native transparent background image asset

Transparent assets, no cutout step

Seedream 5.5 generates images with an alpha channel, so a product shot, a character or a lettering piece arrives ready to drop into a layout. It handles full and partial transparency and keeps fine edges like feathers and claws. Seedream 5.5 works from a text prompt or a reference image.

Seedream 5.5 poster with dense small text rendering

Posters with readable small text

Dense captions, newspaper columns and complex Chinese characters are where image models usually break. In ByteDance's tests, Seedream 5.5 cut severe text corruption to 0.4% and minor corruption to 1.7%, which makes Seedream 5.5 a fit for infographics, newspaper-style pages and posters.

Why reAPI for Seedream 5.5

Seedream 5.5 is built for iterative edits

Seedream 5.5 keeps unedited regions intact, so you can feed each result back in as the next input. That is the workflow ByteDance demonstrated across 100 rounds.

One key, every model

A reAPI key is account-wide. The key you use for Seedream 5.5 also calls Seedream 5.0 Pro, Seedance and GPT Image on the same endpoints.

Pay per Seedream 5.5 image

No subscription: $1 buys 1,000 credits and credits never expire. Seedream 5.5 bills each output image by size plus each reference image, and failed tasks are refunded automatically.

Seedream 5.5 vs Seedream 5.0 Pro

ByteDance benchmarks Seedream 5.5 against Seedream 5.0 Pro, and both Seedream 5.5 and 5.0 Pro run on reAPI. Quality figures come from ByteDance's November 9, 2026 announcement; parameters come from each model's API on reAPI.

Capability

Seedream 5.5 on reAPI

Seedream 5.0 Pro on reAPI

Multi-turn editing

Unedited regions preserved at pixel level, shown across 100 edits

Single and multi-reference image editing

Transparent output

From a prompt or reference images

With exactly one reference image

Text rendering

0.4% severe and 1.7% minor text corruption in ByteDance's test

Rates not given; ByteDance says 5.5 is substantially lower than the previous version

Layer decomposition

Base image plus up to 99 layers, optional text recognition

Base image plus up to 16 layers

Size and references

1K, 1.5K, 2K or exact pixels; up to 10 reference images

Pricing

Per image by size, plus each reference image

Per image by size, plus references after the first

Seedream 5.5 quality figures are ByteDance's own evaluations. Parameters reflect each model's API on reAPI as of November 10, 2026.

Call Seedream 5.5 in three steps

step 01
Create an API key
Sign up and create a key in the dashboard to call Seedream 5.5. Pass it as a Bearer token on every request.
Open
step 02
Try it in the playground
Pick a size, add reference images or switch on layer decomposition, and see the estimated Seedream 5.5 cost before you generate.
Open
step 03
POST to the images endpoint
Send a Seedream 5.5 prompt to /api/v1/images/generations with the model set to doubao-seedream-5-5, then poll GET /api/v1/tasks/:id and read output.image_urls.
Open

docs/api/seedream-5-5

API reference

Drop-in code and the full parameter table.

View full reference

curl -X POST https://reapi.ai/api/v1/images/generations \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "doubao-seedream-5-5",
    "prompt": "a frosted glass perfume bottle, soft studio light",
    "size": "16:9",
    "resolution": "2K"
  }'

Parameter validation failed

Rejected synchronously with the failing field named. Check enum values, ranges, and URL fields — nothing is charged.

Authentication or balance issue

401 means a missing or invalid Bearer key; 402 means the reserve exceeds your balance. Manage keys and credits in the console.

Content or material rejected

Reference material and outputs pass automated moderation. Rejected tasks fail with a clear error and a full refund.

Task failed or timed out

A task that reaches a failed state is never charged — the reserve refunds automatically. Keep the task id and retry when ready.

Frequently asked questions

Common questions about this model.

Seedream 5.5 is ByteDance Seed's next-generation image creation model. Its three headline upgrades are stable multi-turn editing that keeps unedited regions intact at the pixel level, native transparent (RGBA) output, and more realistic images with clearer small text.