Model overview

Provider

Bytedance

Task

Image Editing, Instruction-based Transformation, and In-painting

Architecture

Advanced Diffusion Transformer optimized for semantic understanding and high-resolution consistency.

Resolution

Supports multiple aspect ratios up to 4K clarity, specifically tuned for detailed texture retention.

Key strengths

Precise Instruction Following: Seedream 4.5 excels at understanding complex editing prompts within a 600-word limit.
High Fidelity: Maintains the original image's lighting and geometric structure while applying requested changes.
Versatile Resolutions: Native support for 2K, 4K, and cinematic aspect ratios (e.g., 21:9).
Seamless Integration: Easily integrates into creative pipelines via the Seedream 4.5 Edit Playground.

Seedream 4.5 belongs to the newest generation of image models by Bytedance. Compared to previous iterations, Seedream 4.5 offers significantly improved prompt adherence and clearer details in edited regions. While this page focuses on the Edit mode, users looking to generate images from scratch should use the Seedream 4.5 Text-to-Image model.

How Seedream 4.5 runs on RunComfy

On RunComfy, Seedream 4.5 is hosted as a managed high-performance service, exposed in two complementary ways:

Playground UI

Upload your image, type your edit instructions, and run jobs directly in your browser. Ideal for exploring prompts and testing how Seedream 4.5 interprets specific edits without writing code.

Playground API

Developers can integrate these capabilities directly into their applications using the Playground API. This provides a production-ready endpoint to call Seedream 4.5 programmatically.

👉 Get started with the API here: Seedream 4.5 Edit API

In all cases, inference runs on RunComfy’s cloud GPUs—no local hardware, drivers, or downloads needed.

Input parameters

Seedream 4.5 Edit requires specific inputs to ensure the best editing results. Below are the parameters configured for this model.

Core Inputs

Parameter	Type	Description
prompt	string	The instruction for editing the image. Note: The recommended length is no more than 600 English words. If the prompt is too long, Seedream 4.5 may ignore details and concentrate only on main points, resulting in missing elements.
image_urls	string	Required. The source image(s) you want to edit. Seedream 4.5 uses this as the baseline for modifications.

Resolution Settings

Parameter	Type	Options	Description
resolution	enum	2048x2048 (1:1), 2304x1728 (4:3), 1728x2304 (3:4), 2560x1440 (16:9), 1440x2560 (9:16), 2496x1664 (3:2), 1664x2496 (2:3), 3024x1296 (21:9)	Defines the output quality and aspect ratio. Default is 2048x2048 (1:1). Choosing higher resolutions like 4K allows Seedream 4.5 to generate ultra-detailed textures.

Recommended settings

For Subtle Edits

Keep your prompt concise. If you want to change lighting, specify "Golden hour" or "Neon lights" clearly. Ensure your source image resolution matches the target resolution parameter for the best pixel-perfect mapping.

For Complex Transformations

When asking Seedream 4.5 to change major elements (e.g., "Replace the field with an ocean"), ensure the prompt describes the new scene fully. Remember the 600-word limit to prevent the model from losing focus.

Resolution Choice

For social media, use 1728x2304 (3:4) or 1440x2560 (9:16). For desktop wallpapers or high-quality prints, select 2560x1440 (16:9) or 4K.

Output quality and performance

Seedream 4.5 targets professional-grade outputs with a focus on photorealism and texture accuracy.

On RunComfy, expect:

Resolution: Up to 4K clarity.
Latency: Fast inference times optimized for interactive editing works.
Consistency: Seedream 4.5 minimizes hallucinations, ensuring the unedited parts of your image remain stable.

Recommended use cases

Seedream 4.5 Edit shines across entertainment, film creation, and e-commerce workflows.

Entertainment and creative play

Portrait photography: Higher aesthetic quality with more stable facial lighting and color tones; 2K outputs show fewer artifacts and distortions on small faces.
Group and co-shoot portraits: Better preservation of facial features in two-person and multi-person reference generations, with room for further improvement when subjects look very similar to each other.
Stylized portraits: More consistent skin tones for non-Asian faces in stylized looks, though there is still a gap compared with Nano Pro–level models.
Journal and storybook illustrations: Richer world knowledge for building scenes and props, while still trailing Nano Pro–class models on long-tail world knowledge.

Film and video content creation

Anime-style scenes: With multi-image references, character faces and traits stay more consistent across frames and shots.
Photoreal scenes: In realistic storyboards and key frames, multi-reference setups better preserve character styling and facial identity.

E-commerce and marketing

Main product visuals: Stronger semantic understanding and tighter control over the frame, leading to more reliable interactive edits. Better consistency in product details, color tones, and sharpness, though very small text labels can still occasionally fail. Enhanced aesthetics that reduce overly harsh textures and smearing seen in earlier generations.
Promo visuals with cutouts: Works best when isolating a single main subject, helping generate clean, high-impact compositions.
Selling-point layouts: More reasonable placement and structure for copy and product elements, with improved understanding of e-commerce design rules such as selling-point text layout and product positioning.
Virtual try-on and try-out: More realistic wear and fit proportions plus more consistent detail and color across garments or accessories, with remaining room to improve strict consistency of design, texture, and material in complex try-on scenes.

How Seedream 4.5 compares to Seedream 4.0

Seedream 4.5 delivers an overall upgrade compared to Seedream 4.0, especially in editing stability, small-text clarity, and portrait rendering.

1. Stronger Editing Consistency

Seedream 4.0 could introduce subtle shifts in lighting, structure, or style when applying multiple edits.
Seedream 4.5 greatly improves edit consistency, keeping composition, lighting, and branding elements aligned even under complex, iterative instructions.

2. Sharper Small Text Generation

Seedream 4.0 often struggled with tiny captions, disclaimers, or dense UI labels.
Seedream 4.5 is tuned for crisp small text, making fine print, badges, and layout-heavy designs more legible and production-ready.

3. Enhanced Portrait Beauty and Small-Subject Fidelity

Seedream 4.0 could lose facial nuance or deform small human figures in crowded scenes.
Seedream 4.5 offers more natural portrait beautification and better protection of small characters in the frame, preserving identity, pose, and proportions while enhancing overall aesthetics.

4. Evolving Reasoning and Global Aesthetics

Seedream 4.0 was effective for straightforward edits but could misinterpret multi-step, logic-heavy prompts.
Seedream 4.5 advances both reasoning and visual aesthetics, following complex instructions more faithfully while producing images with richer artistic style, coherent global lighting, and polished, cinematic appeal.

Conclusion

In short, Seedream 4.5 builds on Seedream 4.0 with more reliable edits, clearer details, and higher-end artistic quality, helping creators turn precise ideas into visually refined images.

Seedream 4.5 vs Nano Banana

Overall model performance

Seedream 4.5 vs Seedream 4.0: Seedream 4.5 is a comprehensive upgrade over 4.0, with clear gains on complex prompt handling, the structure and consistency of small faces and small text, object proportion accuracy, and reduced confusion when using multiple reference images.
Seedream 4.5 vs Nano Banana / Nano Banana Pro: Seedream 4.5 generally surpasses Nano Banana (standard), but still has a noticeable gap compared with Nano Banana Pro.

Semantic understanding

Nano Banana Pro has extremely strong semantic understanding and is far ahead of all other models.
Seedream 4.5 still lags Nano Banana Pro in this dimension, especially for very complex or logic-heavy prompts.

Consistency preservation

For structural and aesthetic consistency—such as subject integrity, proportions, and overall style—Seedream 4.5, Nano Banana, and Nano Banana Pro are currently at roughly the same level.

Multi-image input behavior

Nano Banana Pro tends to confuse or blend multiple input images less often than Seedream 4.5.
However, because Nano Banana Pro has much stronger semantic understanding, the overall difference between Seedream 4.5 and Nano Banana Pro is not very large in Elo-style head-to-head evaluations.

Official resources and licensing

Official Website

Explore the research and full capabilities of the Seedream family at the official site: https://seed.bytedance.com/en/seedream4_5

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