Steps are how many denoising iterations Stable Diffusion runs. More is not always better. Most samplers converge by 25–35 steps.
Per-sampler sweet spots
| Sampler | Sweet spot | Above is |
|---|---|---|
| Euler a | 25–30 | Style keeps drifting (non-converging) |
| DPM++ 2M Karras | 25–35 | Essentially unchanged |
| UniPC | 15–20 | Essentially unchanged |
| DDIM | 30–50 | Tiny detail gains |
| Flux Dev | 20–25 | No change |
| Flux Schnell | 2–4 | Collapses |
When to push higher
- Hires fix: 50–80 steps
- Detail-critical product shots: 40 steps
- Complex multi-subject scenes: 35–40 steps
When to go lower
- Batch drafts: UniPC 15 steps
- Schnell: 4 steps is enough
- img2img with low denoise: 15 steps