Stability AI is the company behind Stable Diffusion, one of the most widely adopted open-source AI image generation models in the world. Their flagship product, Stable Diffusion 3.5, is a Multimodal Diffusion Transformer (MMDiT) text-to-image model that delivers significant improvements in image quality, typography rendering, complex prompt understanding, and resource efficiency. The model generates diverse styles ranging from photorealism to artistic renders, supporting high-resolution outputs up to 1 megapixel. Stable Diffusion 3.5 comes in multiple variants: the Large model (8B parameters) for maximum quality, and the Medium model for faster generation with good quality balance. A key differentiator is the open-source nature of Stable Diffusion, which allows developers and researchers to run the models locally on their own hardware, fine-tune them for specific use cases, and integrate them into custom applications without per-image API costs. For those preferring cloud-based access, the Stability AI Developer Platform provides API endpoints with credit-based pricing starting at approximately $0.065 per image for SD 3.5 Large and $0.035 per image for SD 3.5 Medium. The platform also offers Stable Image Ultra, their premium service built on SD 3.5 Large at 8 credits per image, along with additional models for upscaling, inpainting, and image editing. The model is free for non-commercial use and free for commercial use by organizations with annual revenue under $1 million, making it accessible to indie developers and startups. Enterprise licensing is available for larger organizations requiring dedicated support and custom deployment options.