Kimi K3vsGrok 4.3 Beta

Kimi K3
Grok 4.3 Beta
Specifications
Parameters
2.8T
Context window
1M
Benchmarks
Nonsense detection
BullshitBench v2
73%Best
50%
Agentic coding
DeepSWE 1.1
69%
Agentic coding
DeepSWE 1.0
67.5%
Next.js coding
Next.js Evals
92%
Supabase coding
Supabase Evals · with skills
86.4%
Supabase coding
Supabase Evals · no skills
90.9%
Agentic terminal coding
Terminal-Bench 2.1
88.3%
Multi-step tool use
MCP Atlas
84.2%
Professional tool use
JobBench
52.9%
Personal tool use
Toolathlon-Verified
73.2%
Web browsing
BrowseComp
91.2%
Multidisciplinary reasoning
Humanity's Last Exam · no tools
43.5%
Multidisciplinary reasoning
Humanity's Last Exam · with tools
56%
Science
GPQA Diamond
93.5%
Knowledge work
GDPval-AA v2
1668
Chart reasoning
CharXiv Reasoning
84.8%
Multimodal reasoning
MMMU-Pro
81.6%
Community preference
Arena Elo (Text)
1486
Community preference (code)
Arena Elo (Code)
1679
Overview
CompanyMoonshot AISpaceXAI
Release dateJul 16 2026Apr 17 2026
AccessOpen WeightProprietary

Which is better: Kimi K3 or Grok 4.3 Beta?

Kimi K3 leads Grok 4.3 Beta on 1 of the 1 benchmark they both report (BullshitBench v2). Grok 4.3 Beta shipped 90 days before Kimi K3, so benchmark comparisons should account for the intervening progress.

Kimi K3 is open weight, while Grok 4.3 Beta is proprietary.

On BullshitBench v2, Kimi K3 leads at 73% vs Grok 4.3 Beta at 50%.

Frequently asked questions

Kimi K3 was released by Moonshot AI on Jul 16 2026.

Grok 4.3 Beta was released by SpaceXAI on Apr 17 2026.

Kimi K3 is an open weight model released by Moonshot AI. Grok 4.3 Beta is a proprietary model released by SpaceXAI.

Other comparisons