When was Claude 3.5 Sonnet released?

Claude 3.5 Sonnet was released by Anthropic on Jun 20 2024.

When was Kimi K2 (0905) released?

Kimi K2 (0905) was released by Moonshot AI on Sep 5 2025.

Which is better at coding, Claude 3.5 Sonnet or Kimi K2 (0905)?

Kimi K2 (0905) leads on SWE-Bench Verified — Claude 3.5 Sonnet 33.4% vs Kimi K2 (0905) 65.8%.

Which scores higher on GPQA Diamond, Claude 3.5 Sonnet or Kimi K2 (0905)?

Kimi K2 (0905) leads on GPQA Diamond — Claude 3.5 Sonnet 59.4% vs Kimi K2 (0905) 75.1%.

Is Claude 3.5 Sonnet or Kimi K2 (0905) open source?

Kimi K2 (0905) is an open-source / open-weight model released by Moonshot AI. Claude 3.5 Sonnet is a proprietary model released by Anthropic.

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Home/Compare/Claude 3.5 Sonnet vs Kimi K2 (0905)

Claude 3.5 Sonnet vs Kimi K2 (0905)

0 vs 2 benchmarks won

	Anthropic Claude 3.5 Sonnet	Moonshot AI Kimi K2 (0905)
Overview
Company	Anthropic	Moonshot AI
Release date	Jun 20 2024	Sep 5 2025
Model type	—	—
Open source	No	Yes
Specifications
Parameters	—	1T
Context window	—	256k
Benchmarks
Coding SWE-Bench Verified	33.4%	65.8%Best
Science GPQA Diamond	59.4%	75.1%Best
Timeline
Release gap	Claude 3.5 Sonnet shipped 442 days before Kimi K2 (0905)

Which is better: Claude 3.5 Sonnet or Kimi K2 (0905)?

Kimi K2 (0905) leads Claude 3.5 Sonnet on 2 of the 2 benchmarks they both report (SWE-Bench Verified, GPQA Diamond). Claude 3.5 Sonnet shipped 442 days before Kimi K2 (0905), so benchmark comparisons should account for the intervening progress.

Kimi K2 (0905) is an open-source / open-weight model; Claude 3.5 Sonnet is proprietary.

On SWE-Bench Verified, Kimi K2 (0905) leads at 65.8% vs Claude 3.5 Sonnet at 33.4%. On GPQA Diamond, Kimi K2 (0905) leads at 75.1% vs Claude 3.5 Sonnet at 59.4%.

Frequently asked questions

When was Claude 3.5 Sonnet released?: Claude 3.5 Sonnet was released by Anthropic on Jun 20 2024.
When was Kimi K2 (0905) released?: Kimi K2 (0905) was released by Moonshot AI on Sep 5 2025.
Which is better at coding, Claude 3.5 Sonnet or Kimi K2 (0905)?: Kimi K2 (0905) leads on SWE-Bench Verified — Claude 3.5 Sonnet 33.4% vs Kimi K2 (0905) 65.8%.
Which scores higher on GPQA Diamond, Claude 3.5 Sonnet or Kimi K2 (0905)?: Kimi K2 (0905) leads on GPQA Diamond — Claude 3.5 Sonnet 59.4% vs Kimi K2 (0905) 75.1%.
Is Claude 3.5 Sonnet or Kimi K2 (0905) open source?: Kimi K2 (0905) is an open-source / open-weight model released by Moonshot AI. Claude 3.5 Sonnet is a proprietary model released by Anthropic.