The Institute of Foundation Models at Mohamed bin Zayed University of Artificial Intelligence has released K2 Horizon, a family of six open-source AI models ranging from 0.9 billion to 375 billion parameters.
MBZUAI, based in Abu Dhabi, has been steadily building out its K2 model family over the past year.
What the K2 family actually does
The K2 series is built around three core capabilities: general reasoning, long-context handling, and tool utilization.
The lineage here matters. K2 Think launched in September 2025 with 32 billion parameters, designed specifically for reasoning-intensive workloads. By January 2026, the team had scaled that up to K2 Think V2 at 70 billion parameters. K2-V2, released in December 2025, earned top marks on the Artificial Analysis Openness Index, a ranking that evaluates how transparent AI labs actually are about their training data, methods, and model weights.
