Seedream 4.0 API
Vision ModelSeedream 4.0 is ByteDance's leading AI image model for high-res generation and editing, unifying text-to-image and image editing in a single API.
Technical Specs
Capabilities & Features
Seedream 4.0 API - Background
Overview
Seedream 4.0 is ByteDance's flagship AI image model, integrating both image generation and editing into a unified architecture. It is designed to handle complex multimodal tasks, such as knowledge-driven illustration, precise object replacement, and high-fidelity text rendering, all within a single API workflow. The Seedream 4.0 API enables developers to access advanced image processing capabilities, supporting high-resolution outputs and robust prompt-based controls for fine-grained modifications.
Development History
Seedream 4.0 was released in September 2025 as the latest evolution in ByteDance's Seedream series. Building on the strengths of its predecessors, it addresses the limitations of separate generation and editing tools by merging them into one seamless process. The model was developed with extensive internal benchmarking and real-world feedback, resulting in significant improvements in speed, resolution, and prompt adherence. Its debut marked a new standard for AI image APIs, quickly earning top positions on industry leaderboards.
Key Innovations
- Unified architecture for both image generation and editing via a single API
- Advanced prompt-based controls enabling precise, context-aware modifications
- Support for batch operations and 4K resolution outputs to accelerate production workflows
Seedream 4.0 API - Technical Specifications
Architecture
Seedream 4.0 employs a transformer-based encoder for prompt understanding, combined with a diffusion process for pixel-level refinement. The model processes multimodal inputs, including text prompts and reference images, to generate outputs that closely align with user intent. Its training leverages diverse datasets, covering high-resolution photography and synthetic renders, enabling versatility across styles and tasks. The Seedream 4.0 API exposes endpoints for both text-to-image and image-to-image operations, supporting batch processing and various aspect ratios.
Parameters
The exact parameter count is undisclosed, but Seedream 4.0 operates at a large scale, leveraging state-of-the-art transformer and diffusion modules to deliver industry-leading performance and quality.
Capabilities
- High-fidelity image generation and editing through a unified API
- Batch processing of multiple references and outputs for efficient workflows
- Accurate text rendering, object replacement, and style transfer in diverse visual domains
Limitations
- Aspect ratio support is limited to between 1/3 and 3, restricting some custom formats
- Prompt length and complexity may affect output quality; concise, descriptive prompts yield best results
Seedream 4.0 API - Performance
Strengths
- Consistently tops industry leaderboards for image editing and generation, with an ELO score of 1,205
- Delivers up to 30% faster inference compared to previous versions, with strong prompt adherence and aesthetics
Real-world Effectiveness
Seedream 4.0 demonstrates exceptional real-world performance, excelling in tasks that require both creativity and precision. The Seedream 4.0 API is widely adopted for applications in e-commerce, content creation, and education, where high-resolution, context-aware image outputs are critical. Internal and third-party benchmarks confirm its superiority in text rendering, multi-object scene editing, and style transfer, making it a preferred choice for scalable, production-grade deployments.
Seedream 4.0 API - When to Use
Scenarios
- You have an e-commerce platform needing dynamic product visuals. The Seedream 4.0 API enables you to generate and edit product images at scale, such as changing clothing colors or backgrounds while preserving lighting and pose. This leads to higher conversion rates and streamlined content updates.
- You are developing an educational app that requires accurate, visually appealing diagrams and charts. The Seedream 4.0 API excels at knowledge-driven generation, producing labeled timelines, annotated illustrations, and clear instructional graphics, enhancing user engagement and learning outcomes.
- You manage a content creation workflow where rapid prototyping and batch processing are essential. With the Seedream 4.0 API, you can upload multiple references and generate parallel outputs, significantly reducing turnaround time for marketing campaigns or social media assets.
Best Practices
- Use concise, descriptive prompts to maximize output quality and prompt adherence
- Leverage batch processing and environment-based API key management for efficient, scalable deployments