Aleph Alpha Kolibri: How the sovereign German LLM works

Aleph Alpha released Kolibri, an open-weight German/English LLM with 78B total but 3.5B active parameters per token.

Kolibri is a mixture-of-experts LLM with 78.1 billion total parameters and ~3.5 billion active per token, trained on 24 trillion tokens on 768 NVIDIA B200 GPUs. It uses a custom tokenizer requiring 11-24% fewer tokens for German text than alternatives, supports up to 1 million tokens of context, and offers four reasoning effort levels. Aleph Alpha claims it scores above all compared models of its size in both German and English. The model is licensed under Apache 2.0, with weights on Hugging Face, and was trained on European infrastructure with a focus on EU AI Act compliance.