Black Forest Labs released the Klein family with multiple variants designed for different use cases. Klein 4B is the base 4-billion parameter model, while Klein 4B Distilled applies knowledge distillation techniques to reduce inference time while maintaining as much quality as possible. This is a common pattern in modern AI: train a large model, then create faster variants for production deployment.
Knowledge distillation works by training a smaller or more efficient model to mimic the outputs of a larger "teacher" model. The distilled student learns to approximate the teacher's behavior with fewer computational steps. In Klein 4B Distilled's case, the architecture remains at 4B parameters, but the model is optimized to produce good results with fewer inference steps—typically 4 steps compared to the base model's default of 4-8.
The practical result is sub-second generation times for the distilled variant (~1 second) compared to the base model (~1.5 seconds). This 30-50% speed improvement comes with trade-offs. Distilled models typically show slightly reduced fine detail rendering and occasionally less coherent handling of complex prompts. However, for many production use cases, these differences are imperceptible.
Pricing reflects the computational efficiency: Klein 4B Distilled costs roughly 15% less than the base Klein 4B model. Both are available through Replicate and Fal, though the Distilled variant is primarily accessed through Fal's optimized endpoint.
Note: The distilled variant is ideal for high-volume applications where latency matters more than maximum detail. For critical renders where every detail counts, the base 4B model offers a modest quality advantage.