CFG scale (classifier-free guidance) controls how literally Stable Diffusion follows your prompt. Low CFG = more creative; high CFG = more literal.
Reference values
| CFG | Behavior | Best for |
|---|---|---|
| 3–4.5 | Loose, painterly | Artistic / concept work |
| 6–7 | Balanced (default) | General use |
| 8–9 | Strictly literal | Detail-critical scenes |
| 10+ | Over-cooked, distorted | Avoid |
Per-model sweet spots
- SD 1.5: sweet spot 7–8
- SDXL: sweet spot 6–7
- Flux Dev: uses guidance parameter, 3–5
- Flux Schnell: forced 0
Common misconceptions
Higher is better
Above CFG 12 colors over-saturate and forms warp.
CFG affects quality
It does not. CFG sets literal-ness. Quality depends on model, steps and resolution.