Microsoft Finishes Pre-Training MAI-Base-2 With 2.8 Trillion Parameters
Microsoft says pre-training is complete for MAI-Base-2, a mixture-of-experts model with 80 billion active parameters and 2.8 trillion total. It was trained over 38 days from August to September 2026 on 16,000 GB200 GPUs, and unlike MAI-Base-1 it takes in image data, which makes up 18 percent of its 50 trillion training tokens. Post-training is underway and work on MAI-Base-3 has begun.