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Kimi K2 vs Grok 4.3 Beta

2 vs 0 benchmarks won

Moonshot AI
Kimi K2
xAI
Grok 4.3 Beta
Overview
CompanyMoonshot AIxAI
Release dateJul 11 2025Apr 17 2026
Model type
Open sourceYesNo
Specifications
Parameters
1T
Context window
128k
Benchmarks
Science reasoning
GPQA Diamond
75.1%
Software engineering
SWE-Bench Verified
65.8%
Multimodal understanding
MMMU
Timeline
Release gapKimi K2 shipped 280 days before Grok 4.3 Beta

Which is better: Kimi K2 or Grok 4.3 Beta?

Kimi K2 leads Grok 4.3 Beta on 2 of the tracked benchmarks (GPQA Diamond, SWE-Bench Verified, MMMU). Kimi K2 shipped 280 days before Grok 4.3 Beta, so benchmark comparisons should account for the intervening progress.

Kimi K2 is an open-source / open-weight model; Grok 4.3 Beta 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 K2 released?
Kimi K2 was released by Moonshot AI on Jul 11 2025.
When was Grok 4.3 Beta released?
Grok 4.3 Beta was released by xAI on Apr 17 2026.
Is Kimi K2 or Grok 4.3 Beta open source?
Kimi K2 is an open-source / open-weight model released by Moonshot AI. Grok 4.3 Beta is a proprietary model released by xAI.

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