Best open-source alternatives to Midjourney

SillyTavern is a locally installed user interface aimed at people who want a flexible front end for text generation, image generation, and TTS voice models. It presents itself as a single place to work with a wide range of LLM backends and related AI tools, while emphasizing customization and extension support for advanced users and AI hobbyists. The project is designed to run on the user's own machine rather than as a hosted service. The README states that it does not provide online services or track user data, and that it is intended to remain free and open source. It also highlights minimal hardware requirements, with the application running on systems capable of running NodeJS 20 or higher, while heavier local inference workloads depend on the chosen model and backend.

ArtCraft is an IDE for artists focused on interactive AI image and video creation. It is designed for users who want more control than simple prompting, combining visual scene-building tools with model-driven generation workflows. The project emphasizes composing in 2D, staging in 3D, and refining outputs through tools like image editing, background removal, character posing, and asset mixing. It also supports multiple providers and model workflows, including ArtCraft’s own catalog plus Grok, Midjourney, Sora, and World Labs, making it a broad creative workspace for iterative visual production.

ComfyUI is a modular AI creation engine aimed at visual professionals and power users who want precise control over generative workflows. It uses a node-based interface to assemble complex pipelines for image, video, audio, and 3D content creation without requiring code for many common tasks. The project can run locally on desktop systems or via portable/manual installs, and it also offers a paid cloud option. Its workflow system supports many model families, selective re-execution for efficiency, memory offloading for lower-VRAM GPUs, and loading/saving workflows from files and generated assets. It also exposes API endpoints and optional API nodes for external model providers.