Which AI image generator should you use?

We’ve witnessed a sudden explosion of generative AI tools over the past few months. And nowhere is that more true than in the image generator arena. Between free and paid, open-source and proprietary, there are many options out there to choose from. But if you’ve paid some attention to discussions surrounding AI-generated images, you’ve undoubtedly heard of the rivalry between Midjourney vs Stable Diffusion.

While both AI image generators do an excellent job, they differ in terms of customization features, art styles, ease of use, pricing, and more. So in this article, let’s take a look at what separates the two and which one you should use.

If you’ve only recently heard about Midjourney or Stable Diffusion,  it’s because they’re some of the newest AI image generators available today. Both launched to the general public in mid-2022 but with vastly different goals. Midjourney launched as a for-profit service, while Stable Diffusion’s developers released it under an open-source license.

Stable Diffusion’s open nature has made it one of the most customizable and widely available image generators. You can use a basic version of it online, either for free or through a paid subscription. But if you’re looking to fiddle and get the best results possible, you’ll probably want to generate images on your own computer. Frontend software like the Stable Diffusion Web UI project often packs a lot of advanced features and allows you to use custom art models. The downside is that it takes some time and technical skills to set up.

Midjourney, on the other hand, doesn’t take nearly as much effort. We have a dedicated guide on how to use Midjourney, but you simply access it via the Discord chat app. You can add a few parameters to your prompts, but that’s about as far as you can go with customization.

What about the actual quality of the images? You should get reasonably accurate results from both AI image generators. That said, Midjourney’s latest V5 model generates high-quality images that match the text prompt very well. So in that ease of use aspect, it has a slight edge. But if you’re willing to put in the effort to tweak inputs and adjust settings, Stable Diffusion could also match or even exceed Midjourney’s results.

At a passing glance, Midjourney and Stable Diffusion may look like they offer the same feature-set. However, both image generators have some unique strengths and weaknesses.

Take upscaling, for example, which you could previously accomplish using the U1, U2, U3, and U4 buttons in Midjourney. That’s no longer possible as Midjourney’s latest model doesn’t support any upscaling models yet. By contrast, Stable Diffusion’s open nature means you can download several different upscaling models to experiment with. And if your computer has enough video memory, you can also generate higher-resolution images than Midjourney’s current limit of one megapixel.

Here’s a short list of some other feature differences between Midjourney and Stable Diffusion:

• Inpainting and outpainting: With Stable Diffusion, you can use inpainting to tweak certain parts of an existing image. Likewise, outpainting lets you generate new detail outside the boundaries of an existing image. Midjourney doesn’t support either of these editing features yet.
• Image prompts: You can upload an image (or two) as part of your prompt in Midjourney. The bot will combine the image with your text to generate an output that’s visually similar to the input.
• Custom art styles: Midjourney offers an anime-optimized model you can invoke with the --niji parameter. However, Stable Diffusion lets you download custom models trained on a variety of art styles, from realistic to origami.
• Censorship: While the official base Stable Diffusion models don’t allow you to generate explicit images, you can work around these limitations with custom models. This is not possible with Midjourney and you may even find your account banned if your prompts contain explicit or suggestive language.

Keep in mind that you’ll have to use Stable Diffusion on your own hardware to reap most of its benefits. Online tools don’t offer the same level of flexibility, which makes Midjourney just as capable as Stable Diffusion.

As a for-profit company, it’s not surprising that Midjourney imposes some limitations on how often you can use it. Even with a paid Midjourney subscription, you only get a limited amount of free image generation hours each month. The $30 and higher plans do offer unlimited hours of relaxed mode, but that means you’ll have to wait several minutes for each task. Moreover, there’s no free tier or trial whatsoever.

Stable Diffusion works in the exact opposite manner. Its source code is officially available to download, which means you can use it for free. However, you’ll need a beefy computer with a dedicated graphics card. Most models consume at least 4GB of VRAM, so a modern gaming PC fits the bill. But if you don’t already own one, that kind of hardware can easily cost you over a thousand dollars. Luckily, you can use Stable Diffusion online or even in a cloud-based virtual machine like Google Colab if you’re adventurous.

It’s worth noting that the creators of Stable Diffusion also offer a web-based image generation app called DreamStudio. It’s easy to get started with, just like Midjourney, but it comes at a cost. Still, it’s quite a bit cheaper since $10 grants you 1,000 credits. You can also try it for free as all new accounts get 25 credits upon signup.

If you’re looking for a free and easy-to-use option, I’d recommend considering a third alternative like Bing Image Creator instead.

Let’s take a look at some real-world examples to see which AI image generator comes out ahead. For this comparison, I’ll use DreamStudio to generate images via Stable Diffusion as it’s as easy to use as Midjourney. I could perhaps get better results with custom models, but that would take far more effort. So to keep things fair, let’s compare the one-click experience of using Midjourney and Stable Diffusion.

The first image was generated with a rather simplistic prompt: “Star Wars Darth Vader, but make it cyberpunk”. I think both image generators did quite well with the limited information provided, even if they took drastically different approaches.

The next prompt clearly showcases one of Midjourney’s greatest strengths: realism. If you’re looking to generate images that look like they’re grounded in reality, you’ll often get better results than most other AI image generators. While Stable Diffusion matches everything contained in the prompt, it doesn’t live up to the “photorealistic” bit.

For our final example, take a look at how the two image generators handle fantasy prompts. The text prompt asked for a large white serpentine dragon perched atop a rock watching the horizon. Once again, it’s clear that Midjourney can generate more intricate detail. However, if you look closely at the bottom of the image, you’ll notice a series of garbled letters where Midjourney tried to replicate a watermark it learned from its training data.

It’s worth repeating that advanced users can extract far better images from Stable Diffusion than the examples showcased here. However, when comparing the two easiest-to-use options, I’ve found that Midjourney often delivers better results for the same input prompt. Which AI image generator do you prefer?