ComfyUI
The nodal workflow engine for serious diffusion.
Open Source 6–16 GB VRAM
- Min VRAM
- 6 GB
- GPU class
- Mid GPU
- Quant
- FP16
Actually FreeNo SignupOpen SourceWatermark-Free
SwarmUI
Power-user front-end that wraps ComfyUI.
Open Source 8–24 GB VRAMRuns locally
Actually FreeNo SignupOpen SourceWatermark-FreeHobbyist-FriendlyAPIWorkflow Engine
Visit SwarmUIUpdated 2026-05-08 · Direct link
Hardware requirements
Runs locally · High-end GPU (16–24 GB)
Min VRAM
8 GB
Rec. VRAM
24 GB
Min RAM
16 GB
Rec. RAM
32 GB
Disk
60 GB
GPU class
High-end GPU
Inherits ComfyUI backendApple Silicon ✓GPU RequiredQuant: FP16, FP8, GGUF
Designed to orchestrate multiple ComfyUI workers across GPUs/machines.
Screenshot placeholder · SwarmUI
What is SwarmUI?
SwarmUI (formerly StableSwarmUI) is a forms-based front-end that uses ComfyUI as its backend. You get A1111-style ergonomics with ComfyUI's engine, plus distributed multi-GPU and multi-machine generation.
Pros & cons
Pros
- ComfyUI power without the graphs
- Multi-GPU / multi-node orchestration
- Active development
Cons
- Still relies on ComfyUI under the hood
- Smaller community than A1111/ComfyUI
What's actually free?
Free / OSS. Built on top of ComfyUI.
✓ Actually FreeNo SignupOpen SourceWatermark-Free
Alternatives
AUTOMATIC1111 (stable-diffusion-webui)
The original SD power-user webUI.
Open Source 4–12 GB VRAM
- Min VRAM
- 4 GB
- GPU class
- Mid GPU
- Quant
- FP16
Actually FreeNo SignupOpen SourceWatermark-Free
InvokeAI
Production-leaning SD studio with canvas & batch.
Open Source 8–16 GB VRAM
- Min VRAM
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- GPU class
- Mid GPU
- Quant
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