Model · Stability AI · Image-Enhance
Stable Diffusion x4 Upscaler
Stability AI's diffusion-based 4× upscaler. Trades speed for quality — invents plausible high-frequency detail rather than just sharpening, which suits AI-generated images especially well.
- Modality
- Image-Enhance
- License
- CreativeML Open RAIL++-M (Open weights)
- Released
- December 7, 2022
- Last verified
- May 10, 2026
- Runs locally
- Yes
Strengths
- Diffusion-based — generates plausible high-frequency detail
- Pairs naturally with Stable Diffusion image-gen pipelines
- Open-weights, runs in ComfyUI / Automatic1111 with one node
Weaknesses
- Slower than GAN/transformer upscalers — minutes per image on consumer GPUs
- Can hallucinate detail that wasn't in the original — wrong choice for archival or evidentiary work
Try it
| Where | Type | Notes |
|---|---|---|
| Hugging Face | weights | RAIL++ license |
| ComfyUI | local | Native upscaler nodes |
| Replicate | hosted | API key required |
Official sources
- Model card model
Change log
- — Initial entry.
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