Seedream 5.5 Text-to-Image API

bytedance/seedream-v5.5

Seedream 5.5 Text to Image by ByteDance generates images from text prompts with improved photographic realism and aesthetics, native transparent-background output, aspect ratio selection, and 1K, 1.5K, 2K and 3K output tiers. Ready-to-use REST inference API, best performance, no coldstarts, affordable pricing.

Text to Image
Input

Idle

A cozy street-side cafe in Lisbon at golden hour, a barista handing a cup of coffee across the counter, warm natural light, blue azulejo tiles, a chalkboard menu written in English, photorealistic, shot on 35mm

$0.02per run·~50 / $1

ExamplesView all

A cozy street-side cafe in Lisbon at golden hour, a barista handing a cup of coffee across the counter, warm natural light, blue azulejo tiles, a chalkboard menu written in English, photorealistic, shot on 35mm

A cozy street-side cafe in Lisbon at golden hour, a barista handing a cup of coffee across the counter, warm natural light, blue azulejo tiles, a chalkboard menu written in English, photorealistic, shot on 35mm

A young woman reading a book on a sunlit park bench in autumn, golden leaves on the ground, soft afternoon light, natural candid photo, photorealistic, shot on 50mm

A young woman reading a book on a sunlit park bench in autumn, golden leaves on the ground, soft afternoon light, natural candid photo, photorealistic, shot on 50mm

A summer music festival poster: bold headline text "SUNSET SOUNDS 2026", a stylized orange sun over palm trees, a guitar silhouette, small line-up text at the bottom, flat graphic design, vibrant colors

A summer music festival poster: bold headline text "SUNSET SOUNDS 2026", a stylized orange sun over palm trees, a guitar silhouette, small line-up text at the bottom, flat graphic design, vibrant colors

A single glossy red apple, isolated product shot

A single glossy red apple, isolated product shot

A wide panoramic view of snowy mountains at sunrise above a calm alpine lake, photorealistic

A wide panoramic view of snowy mountains at sunrise above a calm alpine lake, photorealistic

A minimalist skincare product shot: a frosted glass serum bottle with a wooden cap on a wet travertine stone, soft morning light, water droplets, shallow depth of field, clean beige background, commercial photography

A minimalist skincare product shot: a frosted glass serum bottle with a wooden cap on a wet travertine stone, soft morning light, water droplets, shallow depth of field, clean beige background, commercial photography

A street food vendor in Bangkok at night grilling skewers, smoke rising, neon signs and string lights behind, candid documentary photo, photorealistic, vertical frame

A street food vendor in Bangkok at night grilling skewers, smoke rising, neon signs and string lights behind, candid documentary photo, photorealistic, vertical frame

A bright Scandinavian living room interior with a linen sofa, oak floor, large window with a view of pine trees, potted plants, soft daylight, architectural photography, wide angle

A bright Scandinavian living room interior with a linen sofa, oak floor, large window with a view of pine trees, potted plants, soft daylight, architectural photography, wide angle

A French bakery window poster with the headline "Pain au chocolat — 2,50 €" in elegant serif lettering, a small line "Fait maison chaque matin", a photo of fresh croissants below, warm cream background, print design

A French bakery window poster with the headline "Pain au chocolat — 2,50 €" in elegant serif lettering, a small line "Fait maison chaque matin", a photo of fresh croissants below, warm cream background, print design

A cute cartoon fox mascot sticker waving, thick white outline, flat vector style, isolated

A cute cartoon fox mascot sticker waving, thick white outline, flat vector style, isolated

Related Models

README

Seedream 5.5

Seedream 5.5 is ByteDance's image model focused on photographic realism, visual aesthetics, and consistent editing. It generates images from text prompts, supports flexible aspect ratios and resolution tiers up to 3K, and can output images with a native transparent background (RGBA).

Why Choose This?

  • Photographic realism and aesthetics
    Built for lifelike detail, natural light, and polished compositions.

  • Native transparent background
    Set background to transparent to get a PNG with an alpha channel straight from the model, with no separate cut-out step.

  • Flexible resolution tiers up to 3K
    Choose 1k or 1.5k for lower-cost generation, 2k for higher-resolution output, or 3k (about 8 megapixels, e.g. 3840×2160 at 16:9) for the most detail.

  • Flexible aspect ratios
    Supports square, portrait, landscape, tall, wide, and cinematic aspect ratios.

  • PNG by default
    Output is PNG unless you ask for jpeg.

Parameters

ParameterRequiredDescription
promptYesPositive prompt for the image generation. Describe the subject, scene, style, lighting, composition, and visual details.
aspect_ratioNoOutput aspect ratio. Options: 1:1, 1:2, 2:1, 1:3, 3:1, 2:3, 3:2, 3:4, 4:3, 4:5, 5:4, 9:16, 16:9, 9:21, or 21:9.
resolutionNoOutput resolution tier: 1k, 1.5k, 2k, or 3k.
output_formatNoOutput image format: png (default) or jpeg.
backgroundNoauto (default), transparent, or opaque. transparent returns an image with an alpha channel and needs png.

How to Use

  1. Write your prompt — Describe the subject, scene, style, lighting, composition, and visual details.
  2. Choose aspect ratio — Select the layout that matches your target format.
  3. Choose resolution — Use 1k or 1.5k for lower-cost drafts, 2k for higher-resolution output, or 3k for print and large displays.
  4. Choose background — Use transparent for cut-out assets such as stickers, product shots, and game or design elements.
  5. Submit — Generate the final image.

Pricing

Pricing is based on selected resolution.

ResolutionCost
1k$0.02
1.5k$0.02
2k$0.027
3k$0.054

Best Use Cases

  • Photorealistic imagery — Product, lifestyle, and portrait visuals with natural detail.
  • Transparent assets — Stickers, icons, characters, and objects ready to place on any background.
  • Marketing visuals — Campaign assets, social media graphics, and promotional images.
  • Print and large displays — 3K output for posters, banners, and wallpapers.
  • Creative concepting — Explore characters, environments, products, and visual styles.
  • Layout-specific assets — Square, portrait, landscape, tall, wide, or cinematic images.

Pro Tips

  • Use detailed prompts with subject, composition, lighting, style, mood, and background details.
  • Choose 1k or 1.5k for faster and lower-cost prompt iteration, and 2k or 3k for final images.
  • Use 9:16 for vertical mobile content and 16:9 for widescreen layouts.
  • For a cut-out, ask for the subject on its own in the prompt and set background to transparent.

Related Models

Note:This website uses AI models provided by third parties. Documentation prices are for reference and may be outdated. The Generate button shows an estimate; the final task charge prevails.

Seedream v5.5 API — Quick start

Grab a WaveSpeedAI API key, then call POST https://api.wavespeed.ai/api/v3/bytedance/seedream-v5.5 with your input as JSON. The endpoint returns a prediction id. Start polling the result endpoint around every 2 seconds, increase the interval for long-running tasks, and stop on any terminal status. On completed, read output values from data.outputs. Examples for Seedream v5.5 below.

HTTP example
set -euo pipefail

: "${WAVESPEED_API_KEY:?Set WAVESPEED_API_KEY}"

REQUEST_BODY=$(cat <<'JSON'
{
    "prompt": "A cinematic shot of a city at sunset, soft golden light",
    "aspect_ratio": "1:1",
    "resolution": "1k",
    "output_format": "png",
    "background": "auto"
}
JSON
)

# 1. Submit the prediction.
SUBMIT_RESPONSE=$(curl --silent --show-error --fail-with-body \
  -X POST "https://api.wavespeed.ai/api/v3/bytedance/seedream-v5.5" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $WAVESPEED_API_KEY" \
  -d "$REQUEST_BODY")

TASK=$(printf '%s' "$SUBMIT_RESPONSE" | jq 'if has("data") then .data else . end')
PREDICTION_ID=$(printf '%s' "$TASK" | jq -r '.id')
if [ -z "$PREDICTION_ID" ] || [ "$PREDICTION_ID" = "null" ]; then
  printf 'Submission response did not contain a prediction id
' >&2
  exit 1
fi
RESULT_URL="https://api.wavespeed.ai/api/v3/predictions/$PREDICTION_ID/result"

# 2. Poll until the prediction finishes.
while true; do
  RESPONSE=$(curl --silent --show-error --fail-with-body "$RESULT_URL" \
    -H "Authorization: Bearer $WAVESPEED_API_KEY")
  RESULT=$(printf '%s' "$RESPONSE" | jq 'if has("data") then .data else . end')
  STATUS=$(printf '%s' "$RESULT" | jq -r '.status')
  case "$STATUS" in
    completed) printf '%s\n' "$RESULT" | jq '.outputs'; break ;;
    failed|cancelled|timeout|deleted) printf '%s\n' "$RESULT" | jq . >&2; exit 1 ;;
    *) sleep 2 ;;
  esac
done
Node.js example
const submitUrl = "https://api.wavespeed.ai/api/v3/bytedance/seedream-v5.5";
const apiKey = process.env.WAVESPEED_API_KEY;
if (!apiKey) throw new Error('Set WAVESPEED_API_KEY');

async function requestJson(url, options = {}) {
  const response = await fetch(url, options);
  if (!response.ok) throw new Error(await response.text());
  return response.json();
}

// 1. Submit the prediction.
const body = await requestJson(submitUrl, {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${apiKey}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
        "prompt": "A cinematic shot of a city at sunset, soft golden light",
        "aspect_ratio": "1:1",
        "resolution": "1k",
        "output_format": "png",
        "background": "auto"
}),
});
const task = body.data ?? body;
if (!task.id) throw new Error("Submission response did not contain a prediction id");
const resultUrl = `https://api.wavespeed.ai/api/v3/predictions/${task.id}/result`;

// 2. Poll until the prediction finishes.
while (true) {
  const resultBody = await requestJson(resultUrl, {
    headers: { "Authorization": `Bearer ${apiKey}` },
  });
  const result = resultBody.data ?? resultBody;
  if (result.status === "completed") {
    console.log(result.outputs);
    break;
  }
  if (["failed", "cancelled", "timeout", "deleted"].includes(result.status)) throw new Error(JSON.stringify(result));
  await new Promise(resolve => setTimeout(resolve, 2000));
}
Python example
import json
import os
import time
from urllib.request import Request, urlopen

api_key = os.environ["WAVESPEED_API_KEY"]
headers = {"Authorization": f"Bearer {api_key}", "Content-Type": "application/json"}
payload = {
    "prompt": "A cinematic shot of a city at sunset, soft golden light",
    "aspect_ratio": "1:1",
    "resolution": "1k",
    "output_format": "png",
    "background": "auto"
}

def request_json(url, data=None):
    request = Request(url, data=data, headers=headers, method="POST" if data else "GET")
    with urlopen(request) as response:
        return json.load(response)

# 1. Submit the prediction.
body = request_json("https://api.wavespeed.ai/api/v3/bytedance/seedream-v5.5", json.dumps(payload).encode())
task = body.get("data", body)
if not task.get("id"):
    raise RuntimeError("Submission response did not contain a prediction id")
result_url = f"https://api.wavespeed.ai/api/v3/predictions/{task['id']}/result"

# 2. Poll until the prediction finishes.
while True:
    result_body = request_json(result_url)
    result = result_body.get("data", result_body)
    status = result.get("status")
    if status == "completed":
        print(result.get("outputs", []))
        break
    if status in {"failed", "cancelled", "timeout", "deleted"}:
        raise RuntimeError(result)
    time.sleep(2)

Seedream v5.5 API — Frequently asked questions

What is the Seedream v5.5 API?

Seedream v5.5 is a ByteDance model for image generation, exposed as a REST API on WaveSpeedAI. Seedream 5.5 Text to Image by ByteDance generates images from text prompts with improved photographic realism and aesthetics, native transparent-background output, aspect ratio selection, and 1K, 1.5K, 2K and 3K output tiers. Ready-to-use REST inference API, best performance, no coldstarts, affordable pricing. You can call it programmatically or try it from the playground above.

How do I call the Seedream v5.5 API?

POST your input parameters to the model's REST endpoint (shown in the API tab of this playground) with your WaveSpeedAI API key in the Authorization header. Submission returns a prediction ID. Poll the result endpoint starting around every 2 seconds, increase the interval for long-running tasks, and stop on any terminal status. The playground generates Python, JavaScript, and cURL examples for submitting requests and polling results. Full request/response shape is documented at https://wavespeed.ai/docs/docs-api/bytedance/bytedance-seedream-v5.5.

How much does Seedream v5.5 cost per run or per second?

Seedream v5.5 starts at $0.02 per run or per second. That figure is the base price — the final charge scales with the parameters you set in the form (output size, length, count, references, or whatever knobs this model exposes), so a higher-quality or larger output costs more than a minimal one. The exact cost for your current input is shown live next to the Generate button before you submit, and the actual per-call charge is recorded on the prediction afterwards.

What inputs does Seedream v5.5 accept?

Key inputs: `prompt`, `aspect_ratio`, `resolution`, `background`, `output_format`. The full JSON schema (types, defaults, allowed values) is rendered above the Generate button and mirrored in the API reference at https://wavespeed.ai/docs/docs-api/bytedance/bytedance-seedream-v5.5.

How do I get started with the Seedream v5.5 API?

Sign up for a free WaveSpeedAI account to claim starter credits, copy your API key from /accesskey, then call the endpoint shown in the API tab of the playground. The playground also auto-generates a code sample in Python, JavaScript, or cURL for the parameters you've set.

Can I use Seedream v5.5 outputs commercially?

Commercial usage rights depend on the model's license, set by its provider (ByteDance). Check the provider's applicable terms and WaveSpeedAI's Terms of Service before commercial use.

llms.txt — bytedance/seedream-v5.5 for AI agents and LLMs