Aleph Alpha logo

Kolibri 1

Aleph AlphaOpen WeightsPending Human Review

Kolibri 1 is Aleph Alpha’s open-weight German-English reasoning and tool-use model, trained from scratch with a German-focused tokenizer and data mixture. Its hybrid-attention mixture-of-experts Transformer has 78B total parameters and approximately 3.46B active per token. The native 262,144-token context can extrapolate to 1,048,576 tokens, but the publisher recommends remaining within the native window for complex tasks and serving efficiency. Apache-licensed weights support private and sovereign deployments. Sparse activation reduces computation without eliminating the memory needed for the full weights; the published knowledge cutoff is June 18, 2026 for both English and German.

2026-10-03
78B total, approximately 3.46B active
Hybrid-attention Mixture-of-Experts Transformer
Apache-2.0

Specifications

Parameters
78B total, approximately 3.46B active
Architecture
Hybrid-attention Mixture-of-Experts Transformer
License
Apache-2.0
Context Window
1,048,576 tokens
Training Data Cutoff
2026-06-18
Type
text
Modalities
text

Benchmark Scores

Advanced Specifications

Model Family
Kolibri
API Access
Not Available
Chat Interface
Not Available
Multilingual Support
Yes
Variants
Kolibri-1FP8 serving
Hardware Support
CUDANVIDIA A100/H100/H200/B200/B300

Capabilities & Limitations

Capabilities
reasoningGerman and Englishtool callinglong context
Known Limitations
Native training context is 262,144; larger windows use extrapolationFull weights require substantially more memory than the active parameter countTraining cutoff limits implicit knowledge
Notable Use Cases
German enterprise assistantsprivate reasoning agentssovereign deployments
Function Calling Support
Yes
Tool Use Support
Yes

Related Models