Use Stable Diffusion / Flux.1 Online! Recommended: SeaArt AI

Introduction

Hello, this is Easygoing.

Today, I'll be doing an in-depth comparison of websites where you can use Stable Diffusion / Flux.1 online!

This article is sponsored by SeaArt AI, but I’ll review these services impartially from a user’s perspective.

Accessing Stable Diffusion / Flux.1 Online

First, for an overview of AI image generators, refer to my previous article.

Among the various image generators, Stable Diffusion / Flux.1 are open-source, allowing many sites to provide online services using these models.

Here, I’ll review some platforms where you can use Stable Diffusion / Flux.1 online!

The Services Being Compared

The services I’ll be comparing are as follows:

Now, let’s briefly look at each platform.

Fal.ai: A Developer-Focused Platform

Fal.ai is one of the most well-known AI platform services.

Primarily aimed at developers, using Fal.ai requires a GitHub account.

Fal.ai offers a wide range of services, from Stable Diffusion / Flux.1 to video and music generation AIs.

Anifusion, which I reviewed previously, uses the Fal.ai platform.

Fal.ai also supports the development of new image generation AI AuraFlow.

Leonardo AI: Art-Focused SDXL

Available Models

• Stable Diffusion XL (including Leonardo AI’s custom models)

Leonardo AI is likely the most well-known site offering Stable Diffusion XL to general users.

Based in Australia, Leonardo AI was acquired by Canva (also in Australia) in July 2024, and its functionality has since been integrated.

Currently, only SDXL-based models are available—no Flux.1 or others—but Leonardo’s highly customized models stand out for their artistic expression.

SeaArt AI: A Broad Range of Free Services

Available Models

• Stable Diffusion 1, Stable Diffusion XL, Stable Diffusion 3.5
• Flux.1[dev], Flux.1[shnell]

SeaArt AI, the main focus here, is based in Singapore.

It provides daily credits for free members, allowing for continued use of many features.

Free members can upscale images to 2048 x 2048 and download in PNG format, delivering beautifully clear image quality.

Tensor Art: Comparable to SeaArt AI

Available Models

• Stable Diffusion 1, Stable Diffusion XL, Stable Diffusion 3.5
• Flux.1[dev], Flux.1[shnell]
• AuraFlow

Launched in July 2023, Tensor Art is a relatively new platform.

While its official location is undisclosed, WHOIS data indicates the domain was registered in Arizona, USA, in May 2023.

Like SeaArt AI, Tensor Art also offers daily free credits.

It provides nearly identical services to SeaArt AI, though upscaling is limited to paid members.

PixAI: Specialized in Anime Style

Available Models

• Stable Diffusion 1, Stable Diffusion XL, Stable Diffusion 3.5

Like TensorArt, PixAI is also a U.S.-based service.

With PixAI, users can apply to receive daily credits.

PixAI is particularly focused on anime models, offering many anime models by default.

Additionally, with SeaArt AI, TensorArt, and PixAI, users can upload their own models, making it easy to use models from sources like Civitai, as long as redistribution is permitted.

Using SeaArt AI!

Let’s walk through how to use SeaArt AI.

SeaArt AI Registration (Free)

To use SeaArt AI, you’ll need an account.

At the top right of SeaArt AI’s homepage, you’ll find the login button.

SeaArt AI supports registration via:

• Google Account
• Discord
• Facebook
• Phone Number

While there’s a button for email registration at the bottom of the page, it didn’t work for me.

If needed, you could consider creating a dedicated Google account for SeaArt AI.

Generating Images with SeaArtAI

Now let’s generate an image in SeaArt AI.

First, click on the “Generate” button at the top center of the page.

The generation screen appears; click “Model Selection” in the top left.

For first-time users, I recommend SeaArt Infinity or the anime model Animagine-XL 3.1. This time, I’ll go with SeaArt Infinity.

Then, choose the aspect ratio and enter your prompt.

Finally, click “Generate” in the top right to generate the image.

Upscaling and Downloading

Hover over the generated image, and options for upscaling or creating videos will appear.

This time, I clicked the upscale button, doubling the resolution.

When you select the upscaled image, this screen appears:

Clicking the download button in the top right lets you save the image.

Free members can generate clear, high-resolution PNG images up to 2048 x 2048!

Other Features in SeaArt AI

SeaArt AI also offers:

• Video generation AI
• Voice generation AI
• Editing and executing ComfyUI workflows

With ComfyUI workflows, you can achieve advanced settings in an online service.

Benefits of Online Services for Local Users

I typically use Stable Diffusion / Flux.1 locally, but online services offer some key advantages.

Sharing ComfyUI Workflows

SeaArt AI has community features, making it easy to share images and workflows.

I often share my workflow on note, but few people use ComfyUI, so it rarely gets noticed.

SeaArt AI lets you easily share ComfyUI workflows, which free members can run with one click—making it widely accessible.

Now Available! Animagine-XL 3.1 + SDXL Refiner Workflow

In this post, I’m sharing the workflow I used to create the illustrations with Animagine-XL 3.1 + SDXL Refiner.

First, make sure to sign up as a free member following the previous instructions. Then, click on this link:

This workflow creates high-quality illustrations, so please be patient. Two images will be generated: the one with higher saturation and sharper outlines is the version with Refiner applied.

See the Refiner effect for yourself—and feel free to download the results!

Drawbacks of Online Services

While convenient, online services also come with some downsides.

Free Members’ Work Is Public

Online services allow you to browse other users’ works and prompts, but as a free member, your work is also public.

This is necessary for platform promotion, but if you’d prefer not to share your work or prompts, you’ll need a paid subscription.

Limited Settings Compared to Local Use

SeaArt AI allows editing and running ComfyUI workflows online, offering fairly advanced customization.

However, it doesn’t support all ComfyUI features. Image quality is especially limited—Flux.1 is restricted to FP8 format to save computing resources, rather than FP16.

The GGUF format released in August 2024 allows for better speed-quality balance locally, so the gap between online and local is shrinking.

Risk of Service Changes or Shutdowns

The biggest downside of online services is the risk of service changes or shutdowns.

Even with a paid subscription, terms and prices may change over time.

Service shutdowns are also problematic, as they would mean losing a familiar interface and potentially losing work saved on the platform.

SeaArt AI allows ComfyUI workflow exports, so the risk of losing knowledge is low, but you may still lose a familiar environment.

Is SeaArt AI Hard to Cancel?

There are reports online that canceling SeaArt AI can be troublesome.

I can’t confirm this firsthand, as I’m a complimentary member, but according to these reports, canceling requires a chat with support rather than a single click on the homepage.

In some cases, replies can take several hours.

As SeaArt AI is based in Singapore, it’s wise to remember that it may operate differently from large Japanese web services.

This advice isn’t limited to SeaArt AI—always check thoroughly when entering payment information on overseas sites.

Summary: Take Advantage of Online Benefits!

• SeaArt AI offers plenty of functionality for free
• You can edit ComfyUI workflows
• Combine the strengths of both online and local setups

Online and local services each have their pros and cons.

Local setups are ideal for personal expression, but online services are useful if you want to try new models or reference other users’ work and workflows.

SeaArt AI offers many free features, so why not give it a try?

Thank you for reading!