How to Access SeeDream 4.0 API (2026)

SeeDream 4.0 is ByteDance's latest text-to-image model, and it has quickly become one of the best image generators available. It produces photorealistic images with exceptional detail, accurate text rendering, and strong prompt adherence. The problem? ByteDance does not offer a straightforward public API. This guide covers every way to access SeeDream 4.0 through an API for your applications.

What Is SeeDream 4.0?

SeeDream (also written as SeedDream) is a diffusion-based image generation model developed by ByteDance's AI research team. Version 4.0 represents a significant leap over its predecessors, with improvements across the board:

Feature	SeeDream 3.0	SeeDream 4.0
Resolution	Up to 1024x1024	Up to 2048x2048
Text rendering	Basic	Near-perfect
Prompt adherence	Good	Excellent
Photorealism	High	State-of-the-art
Style range	Limited	Wide (photo, art, anime, 3D)
Generation speed	~8 seconds	~5 seconds
Human anatomy	Occasional errors	Significantly improved

SeeDream 4.0 competes directly with DALL-E 3, Midjourney v7, Flux 1.1 Pro, and Ideogram 3.0 in quality benchmarks.

API Access Options

ByteDance's API access for SeeDream is primarily available through their Volcano Engine platform (mainly targeting Chinese markets) and through third-party API providers. Here are the main ways to access it:

Option 1: Hypereal AI (Recommended)

Hypereal AI provides direct API access to SeeDream 4.0 alongside 50+ other AI models. It is the simplest way to get started if you want a single API for multiple models.

Pricing: Starting at $0.02 per image

Quick start:

import requests

API_KEY = "your-hypereal-api-key"
BASE_URL = "https://api.hypereal.ai/v1"

response = requests.post(
    f"{BASE_URL}/images/generations",
    headers={
        "Authorization": f"Bearer {API_KEY}",
        "Content-Type": "application/json"
    },
    json={
        "model": "seedream-4.0",
        "prompt": "A cozy coffee shop interior with warm lighting, wooden tables, plants hanging from the ceiling, photorealistic, 8K detail",
        "size": "1024x1024",
        "n": 1
    }
)

data = response.json()
image_url = data["data"][0]["url"]
print(f"Image URL: {image_url}")

Using JavaScript:

const response = await fetch("https://api.hypereal.ai/v1/images/generations", {
  method: "POST",
  headers: {
    Authorization: "Bearer your-hypereal-api-key",
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    model: "seedream-4.0",
    prompt:
      "Professional headshot of a woman in a modern office, natural lighting, shallow depth of field",
    size: "1024x1024",
    n: 1,
  }),
});

const data = await response.json();
console.log(data.data[0].url);

Option 2: Volcano Engine (ByteDance Official)

ByteDance offers SeeDream through their Volcano Engine cloud platform. This is the official first-party option but is primarily aimed at the Chinese market.

Pricing: Approximately 0.06 CNY per image (~$0.008 USD)

Setup steps:

Create an account at volcengine.com
Navigate to the AI section and enable the image generation service
Generate an API key from the console
Use the Volcano Engine SDK

# Volcano Engine SDK example
from volcengine.visual import VisualService

visual_service = VisualService()
visual_service.set_ak("your-access-key")
visual_service.set_sk("your-secret-key")

params = {
    "req_key": "seedream-4.0",
    "prompt": "A futuristic cityscape at sunset with flying vehicles",
    "width": 1024,
    "height": 1024,
    "seed": -1,
}

response = visual_service.text_to_image(params)

Note: The Volcano Engine documentation and dashboard are primarily in Chinese. Payment requires a Chinese bank account or Alipay, which makes it difficult for international developers.

Option 3: Third-Party API Providers

Several API aggregators include SeeDream 4.0:

Provider	SeeDream 4.0	Pricing	OpenAI-Compatible
Hypereal AI	Yes	~$0.02/image	Yes
Fal.ai	Check availability	~$0.03/image	No (custom SDK)
Replicate	Check availability	~$0.03/image	No (custom SDK)
Together AI	No	N/A	N/A
Fireworks AI	No	N/A	N/A

Availability changes frequently as providers add new models. Hypereal AI currently offers the most straightforward access.

API Parameters

When calling SeeDream 4.0 via API, these are the key parameters you can configure:

Parameter	Type	Default	Description
`prompt`	string	Required	Text description of the image to generate
`negative_prompt`	string	""	What to avoid in the generated image
`size`	string	"1024x1024"	Output resolution (512x512 to 2048x2048)
`n`	integer	1	Number of images to generate (1-4)
`seed`	integer	random	Seed for reproducible results
`guidance_scale`	float	7.5	How closely to follow the prompt (1-20)
`steps`	integer	30	Number of diffusion steps (20-50)

Supported Resolutions

Aspect Ratio	Resolution Options
1:1 (Square)	512x512, 768x768, 1024x1024, 2048x2048
16:9 (Landscape)	1024x576, 1280x720, 1920x1080
9:16 (Portrait)	576x1024, 720x1280, 1080x1920
4:3	1024x768, 1280x960
3:4	768x1024, 960x1280

Prompting Tips for SeeDream 4.0

SeeDream 4.0 responds well to detailed, structured prompts. Here are tips for the best results:

Structure your prompts

Subject + Scene + Style + Lighting + Quality modifiers

Example: "A golden retriever puppy sitting in a field of wildflowers,
soft afternoon sunlight, bokeh background, professional pet photography,
Canon EOS R5, 85mm f/1.4"

Use negative prompts

response = requests.post(
    f"{BASE_URL}/images/generations",
    headers={"Authorization": f"Bearer {API_KEY}", "Content-Type": "application/json"},
    json={
        "model": "seedream-4.0",
        "prompt": "Portrait of a young man in a business suit, studio lighting, clean background",
        "negative_prompt": "blurry, distorted, extra fingers, low quality, watermark, text overlay",
        "size": "1024x1024"
    }
)

Text rendering

SeeDream 4.0 excels at rendering text in images. Place text instructions clearly:

"A neon sign reading 'OPEN 24 HOURS' glowing in pink and blue,
mounted on a dark brick wall, rain-wet street reflections below"

SeeDream 4.0 vs. Competitors

Model	Photorealism	Text Rendering	Speed	API Price
SeeDream 4.0	Excellent	Excellent	~5s	~$0.02
DALL-E 3	Very Good	Good	~10s	$0.04
Midjourney v7	Excellent	Good	~15s	$0.05+
Flux 1.1 Pro	Excellent	Very Good	~8s	$0.03
Ideogram 3.0	Very Good	Excellent	~8s	$0.03
Stable Diffusion 3.5	Good	Fair	~4s (local)	Free (local)

Building an Image Generation Pipeline

Here is a complete example of a batch image generation script using SeeDream 4.0:

import requests
import time
import os

API_KEY = os.environ.get("HYPEREAL_API_KEY")
BASE_URL = "https://api.hypereal.ai/v1"

def generate_image(prompt, size="1024x1024", negative_prompt=""):
    """Generate a single image using SeeDream 4.0"""
    response = requests.post(
        f"{BASE_URL}/images/generations",
        headers={
            "Authorization": f"Bearer {API_KEY}",
            "Content-Type": "application/json"
        },
        json={
            "model": "seedream-4.0",
            "prompt": prompt,
            "negative_prompt": negative_prompt,
            "size": size,
            "n": 1
        }
    )

    if response.status_code != 200:
        print(f"Error: {response.status_code} - {response.text}")
        return None

    return response.json()["data"][0]["url"]


# Generate a batch of product images
prompts = [
    "Minimalist wireless earbuds on a white marble surface, soft shadow, product photography",
    "Sleek smartphone standing upright on a wooden desk, natural window light, editorial style",
    "Premium leather wallet open showing card slots, dark background, studio lighting",
]

for i, prompt in enumerate(prompts):
    url = generate_image(prompt, negative_prompt="blurry, low quality, watermark")
    if url:
        print(f"Image {i + 1}: {url}")
    time.sleep(1)  # Rate limiting

Wrapping Up

SeeDream 4.0 is one of the strongest image generation models available today, with exceptional photorealism and text rendering capabilities. While ByteDance's direct API access through Volcano Engine can be challenging for international developers, third-party providers make it accessible with standard API patterns.

Hypereal AI offers the easiest path to SeeDream 4.0 with an OpenAI-compatible API, transparent pricing, and access to 50+ other AI models for image, video, and audio generation.

Try Hypereal AI free -- 35 credits, no credit card required. SeeDream 4.0 is available today.