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

Claude Sonnet 4.6 vs Kimi K2 Thinking

Anthropic
Claude Sonnet 4.6
Moonshot AI
Kimi K2 Thinking
Overview
CompanyAnthropicMoonshot AI
Release dateFeb 17 2026Nov 6 2025
AccessProprietaryOpen Weight
Specifications
Parameters
1T
Context window
256k
Benchmarks
Nonsense detection
BullshitBench v2
91%
Coding
SWE-Bench Verified
79.6%Best
71.3%
Agentic coding
CursorBench v3.1
49%
Next.js coding
Next.js Evals
58%
Multi-step tool use
MCP Atlas
69.5%
Multidisciplinary reasoning
Humanity's Last Exam · no tools
33.2%
Abstract reasoning
ARC-AGI-2
58.3%
Science
GPQA Diamond
89.9%
Agentic computer use
OSWorld-Verified
72.5%
Agentic financial analysis
Finance Agent v2
51%
Knowledge work
GDPval-AA
1676
Chart reasoning
CharXiv Reasoning
72.4%
Multimodal reasoning
MMMU-Pro
74.5%
Spatial reasoning
Blueprint-Bench 2
6.7%
Long context
MRCR v2 (8-needle) · 128k average
84.9%
Community preference (code)
Arena Elo (Code)
1521
Timeline
Release gapKimi K2 Thinking shipped 103 days before Claude Sonnet 4.6

Which is better: Claude Sonnet 4.6 or Kimi K2 Thinking?

Claude Sonnet 4.6 leads Kimi K2 Thinking on 1 of the 1 benchmark they both report (SWE-Bench Verified). Kimi K2 Thinking shipped 103 days before Claude Sonnet 4.6, so benchmark comparisons should account for the intervening progress.

Claude Sonnet 4.6 is proprietary, while Kimi K2 Thinking is open weight.

On SWE-Bench Verified, Claude Sonnet 4.6 leads at 79.6% vs Kimi K2 Thinking at 71.3%.

Frequently asked questions

Claude Sonnet 4.6 was released by Anthropic on Feb 17 2026.

Kimi K2 Thinking was released by Moonshot AI on Nov 6 2025.

Claude Sonnet 4.6 leads on SWE-Bench Verified — Claude Sonnet 4.6 79.6% vs Kimi K2 Thinking 71.3%.

Claude Sonnet 4.6 is a proprietary model released by Anthropic. Kimi K2 Thinking is an open weight model released by Moonshot AI.

Other comparisons