adtestbench Higgsfield

AI news · Microsoft · models

Microsoft finishes MAI-Base-2, a 2.8 trillion parameter model

Microsoft says its own base model beats every open-weight rival it measured, and that it can license the weights to partners.

By Alexandre S. , 10:30 UTC

Microsoft is building large AI models of its own in earnest. In a blog post on Thursday 15 October 2026, Microsoft AI said it had finished pre-training MAI-Base-2. Pre-training is the long, expensive opening phase of building a model, in which it reads vast amounts of material and picks up how language and ideas fit together.

Retro-futurist illustration: a striped sunset over a grid horizon under a starry sky, with a chip motif standing on the horizon.
Drawn by adtestbench from “Frontier Pre-training at Microsoft AI”,

The model holds 2.8 trillion parameters, the numbers it adjusts as it learns. Only 80 billion of them work on each token, a word or piece of a word.

The claims are bold. Microsoft says it beats every open-weight model (one whose files anyone can download) that it ran through its own private question sets, kept out of training. It puts its pre-training efficiency at 4 to 12 times that of DeepSeek-V4-Pro-Base, the strongest open base model in its comparison.

Because none of its training data came from distilling other models (learning by copying their answers), Microsoft says it can offer the weights under licence to trusted partners through Foundry, its AI platform for businesses, Constellation Research reports.

At a staff meeting, Microsoft AI chief Mustafa Suleyman said the base model beats the one behind OpenAI’s GPT 5.6 Sol, Business Insider reports. He added that it took a quarter of OpenAI’s computing power to train.

Microsoft’s licensing plan points businesses on its cloud to a large in-house base model they can tune on their own data.