Microsoft MAI-Thinking-1
Microsoft MAI-Thinking-1
Microsoft's first in-house reasoning model. Announced at Microsoft Build 2026 on June 2, 2026. ~1T total parameters, 35B active via sparse Mixture of Experts. Trained entirely on commercially licensed data — no distillation from OpenAI or other third-party models, and no AI-generated content in pre-training. Runs on Microsoft's Maia 200 inference accelerators inside Azure.
Architecture
Sparse MoE. ~1T total parameters, 35B active per token. 256K token context window. Supports function calling and system instructions. Compatible with the standard Chat Completions API.
Benchmarks
| Benchmark | Score |
|---|---|
| AIME 2025 | 97.0% |
| AIME 2026 | 94.5% |
| SWE-Bench Pro | ~53% (competitive with Claude Opus 4.6) |
| Human preference (blind side-by-side, 1,276 tasks) | Preferred over Claude Sonnet 4.6 |
Strong in mathematical and scientific reasoning for its weight class. Slightly below the very top tier on coding benchmarks (Claude Opus 4.8, GPT-5.5).
Training
Ground-up training on enterprise-grade, commercially licensed data. No distillation from third-party models. AI-generated synthetic content explicitly excluded from pre-training. Microsoft describes this as enabling clean enterprise licensing without legal ambiguity.
Hardware
Runs on Maia 200 — Microsoft's second-generation in-house AI inference accelerator. Specs: TSMC 3nm process, 216GB HBM3e memory, 7 TB/s memory bandwidth, 140B+ transistors, >10 petaflops FP4 / >5 petaflops FP8, 750W TDP. Four chips per tray with direct non-switched interconnects; scales to 6,144 accelerators. Deployed in Azure US Central (Iowa) and US West 3 (Phoenix), with Italy, Australia, and South Korea expanding next.
MAI Family
MAI-Thinking-1 is the reasoning flagship of a 7-model MAI family announced at Build 2026. Known members:
| Model | Role |
|---|---|
| MAI-Thinking-1 | Reasoning flagship |
| MAI-Code-1-Flash | 5B coding model, live in GitHub Copilot |
| MAI-Image-2.5 | Multimodal image generation and editing |
| MAI-Voice-2 | Text-to-speech and voice cloning |
| MAI-Transcribe-1.5 | Speech-to-text |
Project Polaris
Project Polaris is a coding-specialized MAI model (companion to MAI-Thinking-1) being positioned as the GitHub Copilot default engine. Replaces GPT-4 Turbo as the default model for all GitHub Copilot subscribers starting August 2026. Three-month fallback period offered for teams that want to stay on GPT-4.
MAI-Code-1-Flash (5B) is already live in the Copilot model picker as of June 2, 2026, scoring 51.2% on SWE-Bench Pro vs. 35.2% for Claude Haiku 4.5.
Availability
- Azure AI Foundry (enterprise, private preview at launch)
- MAI Playground (public preview planned)
- OpenRouter, Fireworks AI, Baseten (third-party API access)
- GitHub Copilot model picker (MAI-Code-1-Flash)
Pricing
Not disclosed at launch.
Strengths
- No licensing ambiguity: fully commercially licensed training data, no OpenAI distillation — clean for enterprise IP-sensitive deployments.
- Strong math/reasoning: 97.0% AIME 2025, 94.5% AIME 2026 — top-tier scores.
- Native Azure integration: runs on Maia 200 inside Azure, which reduces latency and lowers routing cost vs. third-party model calls.
- 256K context: sufficient for most enterprise document-processing workloads.
Weaknesses
- Context window (256K) is smaller than Nemotron 3 Ultra or claude-opus-4-8 (both 1M).
- SWE-Bench Pro score (~53%) trails the current frontier (claude-opus-4-8 ~69%, MiniMax M3 59%).
- Not open-weights; Microsoft controls weights and deployment.
- Pricing not yet disclosed — hard to model cost vs. alternatives.
Use Cases
Best for: enterprise reasoning tasks on Azure, math/science workflows, organizations that need a model with clean commercial training provenance. Will be the default Copilot coding engine from August 2026 via Project Polaris.
Not ideal for: very long context tasks over 256K tokens (use claude-opus-4-8 or nvidia-nemotron-3-ultra), pure coding benchmark maximization.
Related
claude-opus-4-8 · claude-sonnet-4-6 · agentic-workflows · evals · extended-thinking
Sources
- Introducing MAI-Thinking-1 — Microsoft AI
- Microsoft Build 2026: MAI Keynote Transcript — Microsoft AI
- MAI-Thinking-1 & MAI-Code-1-Flash Developer Guide — DEV Community
- GitHub Copilot Replaces GPT-4 With Project Polaris — TechTimes
- Maia 200: The AI accelerator built for inference — Microsoft Blog
- Microsoft Maia 200 specs — Tom's Hardware