Grok 4 vs MAI-1-preview

xAI · US  |  Microsoft · US · Updated June 2026

Quick verdict

Pick Grok 4 for 256k context with native tool use or real-time data via x integration. Pick MAI-1-preview for microsoft's first fully in-house, end-to-end foundation model - a historic break from relying solely on openai or ranked in the top 15 on lm arena at launch. On a tight budget at scale, MAI-1-preview is the value pick.

Grok 4 (xAI) and MAI-1-preview (Microsoft) are two of the models people most often weigh against each other in 2026. Grok 4 is xAI's 2M-context model with live data access and strong reasoning chops. MAI-1-preview is microsoft's first fully in-house foundation model - a strategic break from sole reliance on OpenAI, trained on ~15,000 H100 GPUs. They diverge most on price and context window — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecGrok 4MAI-1-preview
ProviderxAI (US) Microsoft (US)
ReleasedJuly 9, 2025 August 28, 2025
Context window256K (~384 pages) 128K (~192 pages)
Price (in/out)$3/$15 per 1M tokens Not published
Open weight?No — API only No — API only
Modalitiestext, image, code text, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

256K context with native tool use

Grok 4

Its 256K window holds about 2× more than MAI-1-preview's 128K in a single prompt.

Real-time data via X integration

Grok 4

XAI's 2M-context model with live data access and strong reasoning chops — and it carries the larger 256K context.

Strong academic reasoning

Grok 4

MAI-1-preview is comparatively weak here — distinct from Microsoft's later MAI-Thinking-1 reasoning model - an earlier, more general-purpose entry

Microsoft's first fully in-house, end-to-end foundation model - a historic break from relying solely on OpenAI

MAI-1-preview

Grok 4 is comparatively weak here — smaller ecosystem than OpenAI/Google

Ranked in the top 15 on LM Arena at launch

MAI-1-preview

Microsoft's first fully in-house foundation model - a strategic break from sole reliance on OpenAI, trained on ~15,000 H100 GPUs — and it is the newer of the two.

Trained on roughly 15,000 NVIDIA H100 GPUs, a genuine internal infrastructure investment

MAI-1-preview

MAI-1-preview lists trained on roughly 15,000 NVIDIA H100 GPUs, a genuine internal infrastructure investment among its strengths; Grok 4 does not.

Lowest cost at scale

MAI-1-preview

Its weights are open, so at volume you pay for your own hardware instead of Grok 4's $3/$15 per 1M tokens.

Largest single-prompt input

Grok 4

Its 256K window is about 2× larger than MAI-1-preview's 128K, fitting roughly 384 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

MAI-1-preview

At Not published it undercuts Grok 4, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

Grok 4

Larger 256K window fits more in one prompt.

Anyone whose priority is 256k context with native tool use

Grok 4

It is specifically built for that.

Anyone whose priority is microsoft's first fully in-house, end-to-end foundation model - a historic break from relying solely on openai

MAI-1-preview

That is its strongest area.

Grok 4: where it fits

XAI's 2M-context model with live data access and strong reasoning chops. Released July 9, 2025 by xAI, it is built for 256K context with native tool use, real-time data via X integration, strong academic reasoning, and no long-context surcharge.

Its trade-offs are real: smaller ecosystem than OpenAI/Google, and less independent benchmark coverage. At $3 in / $15 out per million tokens, it sits in the mid price band.

MAI-1-preview: where it fits

Microsoft's first fully in-house foundation model - a strategic break from sole reliance on OpenAI, trained on ~15,000 H100 GPUs. Released August 28, 2025 by Microsoft, it is built for microsoft's first fully in-house, end-to-end foundation model - a historic break from relying solely on OpenAI, ranked in the top 15 on LM Arena at launch, trained on roughly 15,000 NVIDIA H100 GPUs, a genuine internal infrastructure investment, and rolled into Copilot alongside OpenAI models, giving Microsoft a real second option.

Its trade-offs: a 'preview' release, not yet positioned as Microsoft's primary Copilot model, no public per-token API pricing - not sold as a standalone product, and distinct from Microsoft's later MAI-Thinking-1 reasoning model - an earlier, more general-purpose entry.

The bottom line for this matchup

Grok 4 and MAI-1-preview overlap enough that the right pick depends on your specific job. MAI-1-preview costs less per token; Grok 4 holds the larger context; and each leads in its own area — Grok 4 for 256k context with native tool use, MAI-1-preview for microsoft's first fully in-house, end-to-end foundation model - a historic break from relying solely on openai. Rather than crowning one, run the same hard task through both once and let the results decide.

Want both Grok 4 and MAI-1-preview without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.

See pricing

Frequently asked questions

Is Grok 4 or MAI-1-preview better for coding?

Public SWE-Bench figures are not available for either model, so the honest test is your own repository — run an identical real bug through both. By design, Grok 4 leans toward 256k context with native tool use while MAI-1-preview leans toward microsoft's first fully in-house, end-to-end foundation model - a historic break from relying solely on openai, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Grok 4 or MAI-1-preview?

MAI-1-preview is cheaper — $3/$15 per 1M tokens vs Not published.

Which has the bigger context window?

Grok 4 — 256K vs 128K, about 2× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both Grok 4 and MAI-1-preview together?

Yes — a multi-model platform like LumiChats gives you Grok 4, MAI-1-preview and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.

Which is newer, Grok 4 or MAI-1-preview?

MAI-1-preview — released August 28, 2025, about 50 days after Grok 4.

Related comparisons

Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.