Kimi K2.5 vs MAI-Thinking-1

Moonshot AI · China  |  Microsoft · US · Updated June 2026

Quick verdict

Pick Kimi K2.5 for native multimodal reasoning and visual coding or agentic tool-calling and self-directed multi-step work. Pick MAI-Thinking-1 for very strong math reasoning (aime 2025 97%, aime 2026 94.5%) or microsoft's first in-house flagship reasoner, trained without openai distillation. Choose Kimi K2.5 if you need self-hosting or data privacy; MAI-Thinking-1 if you want a managed API.

Kimi K2.5 (Moonshot AI, China) and MAI-Thinking-1 (Microsoft, US) line up two different AI ecosystems against each other — a comparison that is as much about cost philosophy and openness as raw capability. Kimi K2.5 is moonshot's open-weight multimodal model at $0.60/$2.50 with a 256K window — strong visual coding and agentic work, since superseded by K2.6/K2.7. MAI-Thinking-1 is microsoft's first fully in-house flagship reasoning model — a Claude-class reasoner built independently to cut its OpenAI dependence. They diverge most on price, context window and open vs. closed weights — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecKimi K2.5MAI-Thinking-1
ProviderMoonshot AI (China) Microsoft (US)
ReleasedJanuary 27, 2026 June 2, 2026
Context window256K (~393 pages) 256K (~384 pages)
Price (in/out)$0.6/$2.5 per 1M tokens Not published
Open weight?Yes — self-hostable No — API only
Modalitiestext, image, code text, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Native multimodal reasoning and visual coding

Kimi K2.5

Moonshot's open-weight multimodal model at $0.60/$2.50 with a 256K window — strong visual coding and agentic work, since superseded by K2.6/K2.7 — and its weights are open while MAI-Thinking-1 is API-only.

Agentic tool-calling and self-directed multi-step work

Kimi K2.5

Kimi K2.5 lists agentic tool-calling and self-directed multi-step work among its strengths; MAI-Thinking-1 does not.

Open-weight (Modified-MIT) — self-hostable at 256K context

Kimi K2.5

Open weights make this possible at all — MAI-Thinking-1 is API-only, so it cannot leave the vendor's servers.

Very strong math reasoning (AIME 2025 97%, AIME 2026 94.5%)

MAI-Thinking-1

Microsoft's first fully in-house flagship reasoning model — a Claude-class reasoner built independently to cut its OpenAI dependence — and it is the newer of the two.

Microsoft's first in-house flagship reasoner, trained without OpenAI distillation

MAI-Thinking-1

MAI-Thinking-1 lists microsoft's first in-house flagship reasoner, trained without OpenAI distillation among its strengths; Kimi K2.5 does not.

Efficient reasoning at low token cost for its class

MAI-Thinking-1

MAI-Thinking-1 lists efficient reasoning at low token cost for its class among its strengths; Kimi K2.5 does not.

Lowest cost at scale

MAI-Thinking-1

Its weights are open, so at volume you pay for your own hardware instead of Kimi K2.5's $0.6/$2.5 per 1M tokens.

Which should you pick?

A cost-sensitive startup shipping high volume

MAI-Thinking-1

At Not published it undercuts Kimi K2.5, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

Kimi K2.5

Larger 256K window fits more in one prompt.

A team with data-privacy or self-hosting needs

Kimi K2.5

Open weights let you run it on your own hardware; MAI-Thinking-1 is API-only.

Anyone whose priority is native multimodal reasoning and visual coding

Kimi K2.5

It is specifically built for that.

Anyone whose priority is very strong math reasoning (aime 2025 97%, aime 2026 94.5%)

MAI-Thinking-1

That is its strongest area.

An enterprise with regional data-residency rules

MAI-Thinking-1 or Kimi K2.5

Origin (China vs US) affects where data is processed and which compliance regime applies — check the provider's terms for your region.

Kimi K2.5: where it fits

Moonshot's open-weight multimodal model at $0.60/$2.50 with a 256K window — strong visual coding and agentic work, since superseded by K2.6/K2.7. Released January 27, 2026 by Moonshot AI, it is built for native multimodal reasoning and visual coding, agentic tool-calling and self-directed multi-step work, open-weight (Modified-MIT) — self-hostable at 256K context, and vendor reports around 76.8% on its own SWE-agent coding harness.

Its trade-offs are real: its coding score uses Moonshot's own harness, not the standard SWE-Bench Verified protocol, superseded within Moonshot's line by Kimi K2.6 and K2.7, openRouter shows a promo price below Moonshot's $0.60/$2.50 list, and image input but no audio or video. At $0.6 in / $2.5 out per million tokens, it sits in the budget price band.

MAI-Thinking-1: where it fits

Microsoft's first fully in-house flagship reasoning model — a Claude-class reasoner built independently to cut its OpenAI dependence. Released June 2, 2026 by Microsoft, it is built for very strong math reasoning (AIME 2025 97%, AIME 2026 94.5%), microsoft's first in-house flagship reasoner, trained without OpenAI distillation, efficient reasoning at low token cost for its class, and competitive with Claude Opus 4.6 on SWE-Bench Pro (vendor-reported).

Its trade-offs: closed and in private preview — no open weights, no published pricing, thin availability, and benchmarks are largely self-reported.

The bottom line for this matchup

The defining split here is open vs. closed. Kimi K2.5 gives you weights you control — self-host it, fine-tune it, keep data in-house, pay only for hardware. MAI-Thinking-1 gives you a managed, always-updated API with no infrastructure to run. Teams with GPUs, privacy requirements, or huge volume often favour the open model; teams that want zero ops and the latest capabilities favour the closed one. Capability is close enough that this operational question, not the benchmark, usually decides it.

Want both Kimi K2.5 and MAI-Thinking-1 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 Kimi K2.5 or MAI-Thinking-1 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, Kimi K2.5 leans toward native multimodal reasoning and visual coding while MAI-Thinking-1 leans toward very strong math reasoning (aime 2025 97%, aime 2026 94.5%), and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Kimi K2.5 or MAI-Thinking-1?

Kimi K2.5 is open-weight, so self-hosting means no per-token fee (you pay for hardware instead), while MAI-Thinking-1 is API-metered at Not published. For most teams without GPUs, the API model is cheaper to start; at very high volume, self-hosting can win.

Which has the bigger context window?

Effectively neither — 256K vs 256K is a difference of a few percent. Remember advertised ≠ usable: recall typically degrades before the ceiling.

Can I use both Kimi K2.5 and MAI-Thinking-1 together?

Yes — a multi-model platform like LumiChats gives you Kimi K2.5, MAI-Thinking-1 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, Kimi K2.5 or MAI-Thinking-1?

MAI-Thinking-1 — released June 2, 2026, about 4 months after Kimi K2.5.

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.