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Kimi Linear vs Grok 4

Moonshot AI Kimi Linear vs xAI Grok 4 — side-by-side specs.

Moonshot AI
Kimi Linear
xAI
Grok 4
Overview
CompanyMoonshot AIxAI
Release dateOct 2025Jul 9 2025
Model type
Open sourceYesNo
Specifications
Parameters
48B
Context window
Benchmarks
Science reasoning
GPQA Diamond
Software engineering
SWE-Bench Verified
Multimodal understanding
MMMU
Timeline
Release gapGrok 4 shipped 84 days before Kimi Linear

Which is better: Kimi Linear or Grok 4?

Kimi Linear and Grok 4 do not have directly comparable benchmark scores published on GPQA Diamond, SWE-Bench Verified, or MMMU. Grok 4 shipped 84 days before Kimi Linear, so benchmark comparisons should account for the intervening progress.

Kimi Linear is an open-source / open-weight model; Grok 4 is proprietary.

Direct benchmark comparisons are unavailable — at least one of these models has not published scores on GPQA Diamond, SWE-Bench Verified, or MMMU.

Frequently asked questions

When was Kimi Linear released?
Kimi Linear was released by Moonshot AI on Oct 2025.
When was Grok 4 released?
Grok 4 was released by xAI on Jul 9 2025.
Is Kimi Linear or Grok 4 open source?
Kimi Linear is an open-source / open-weight model released by Moonshot AI. Grok 4 is a proprietary model released by xAI.

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