Seedream 4.0 API

About Seedream 4.0

Unified image generation and editing with up to 14 reference images, batch sets of up to 15, and 1K to 4K output at one flat per-image price.

Also known as ByteDance Seedream 4.0

Seedream 4.0 specs

Model ID

seedream-4-0

Provider

ByteDance

Category

Image Generation

Released

Sep 9, 2025

Input

TextImage

Output

Image

Region

Malaysia

Endpoints

POST/v1/images/generations

Alternate model IDs

bytedance/seedream-4.0seedream-4.0seedream-4seedream-4-0-250828

Seedream 4.0 API pricing

Live pay-as-you-go rates from the EmpirioLabs catalog. You are billed only for what you use, with no monthly minimum.

How to call the Seedream 4.0 API

Seedream 4.0 runs through POST /v1/images/generations. The request returns a job_id right away; poll GET /v1/jobs/{job_id} until the job completes and read the output URLs from the result. Or add "sync": true to skip polling: the request stays open and returns the finished OpenAI-style image response directly, so OpenAI SDKs work as-is. Get an API key from the EmpirioLabs dashboard.

curl https://api.empiriolabs.ai/v1/images/generations \
  -H "Authorization: Bearer $EMPIRIOLABS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "seedream-4-0",
    "prompt": "Describe what you want Seedream 4.0 to generate."
  }'

curl https://api.empiriolabs.ai/v1/jobs/JOB_ID \
  -H "Authorization: Bearer $EMPIRIOLABS_API_KEY"

import requests

response = requests.post(
    "https://api.empiriolabs.ai/v1/images/generations",
    headers={"Authorization": "Bearer YOUR_EMPIRIOLABS_API_KEY"},
    json={
        "model": "seedream-4-0",
        "prompt": "Describe what you want Seedream 4.0 to generate.",
    },
)
job = response.json()

# Generation runs as an async job. Poll until it completes.
import time
while True:
    status = requests.get(
        f"https://api.empiriolabs.ai/v1/jobs/{job['job_id']}",
        headers={"Authorization": "Bearer YOUR_EMPIRIOLABS_API_KEY"},
    ).json()
    if status.get("status") in ("completed", "failed"):
        print(status)
        break
    time.sleep(5)

Seedream 4.0 API parameters

Request parameters supported by the Seedream 4.0 API on EmpirioLabs. Defaults apply when a field is omitted.

Good to know

Text-to-image, single-reference editing, and multi-reference generation from up to 14 input images, plus batch sets of up to 15 related images. Every size bills at the same flat per-image rate, and input reference images are free.

Output

• 1K, 2K, or 4K tiers, or an explicit size between 0.92MP and 16.78MP total pixels. JPEG output.
• A fast prompt-optimization mode trades a little quality for lower latency.

Batch mode

• sequential_image_generation auto generates a cohesive set; you are billed only for images actually returned.

Content safety

• Generated images pass an automated content-safety check. An image flagged as explicit is not returned. Because the image is generated before the check runs, a flagged generation is still billed.

Seedream 4.0 API: common questions

How much does the Seedream 4.0 API cost?

On EmpirioLabs, Seedream 4.0 is billed pay as you go: Standard $0.060 per image. The live rate card on this page always matches what the API charges.

Which endpoint does Seedream 4.0 use?

Seedream 4.0 is served through POST /v1/images/generations on api.empiriolabs.ai with standard bearer-token authentication.

Can I try Seedream 4.0 in the browser before integrating?

Yes. The EmpirioLabs playground runs Seedream 4.0 in the browser with the same parameters the API exposes, so you can test prompts before writing code.

How do I get a Seedream 4.0 API key?

Create an EmpirioLabs account, then generate a key under API Keys in the dashboard. Billing is pay-as-you-go credits, so you only pay for the requests you make.