AI Model Release Tracker - Timeline of Major AI Models from 2022-2026

Kimi K2.6 vs Grok 4.3 Beta

Moonshot AI
Kimi K2.6
SpaceXAI
Grok 4.3 Beta
Overview
CompanyMoonshot AISpaceXAI
Release dateApr 21 2026Apr 17 2026
AccessOpen WeightProprietary
Specifications
Parameters
1T
Context window
256k
Benchmarks
Nonsense detection
BullshitBench v2
65%Best
50%
Coding
SWE-Bench Verified
80.2%
Agentic coding
CursorBench v3.1
47.6%
Next.js coding
Next.js Evals
67%
Competitive coding
LiveCodeBench
89.6%
Science
GPQA Diamond
90.5%
Community preference (code)
Arena Elo (Code)
1513
Timeline
Release gapGrok 4.3 Beta shipped 4 days before Kimi K2.6

Which is better: Kimi K2.6 or Grok 4.3 Beta?

Kimi K2.6 leads Grok 4.3 Beta on 1 of the 1 benchmark they both report (BullshitBench v2). Grok 4.3 Beta shipped 4 days before Kimi K2.6, so benchmark comparisons should account for the intervening progress.

Kimi K2.6 is open weight, while Grok 4.3 Beta is proprietary.

On BullshitBench v2, Kimi K2.6 leads at 65% vs Grok 4.3 Beta at 50%.

Frequently asked questions

Kimi K2.6 was released by Moonshot AI on Apr 21 2026.

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

Kimi K2.6 is an open weight model released by Moonshot AI. Grok 4.3 Beta is a proprietary model released by SpaceXAI.

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