Claude Sonnet 5 vs Kimi K2
Anthropic Claude Sonnet 5 | Moonshot AI Kimi K2 | |
|---|---|---|
| Overview | ||
| Company | Anthropic | Moonshot AI |
| Release date | Jun 30 2026 | Jul 11 2025 |
| Access | Proprietary | Open Weight |
| Specifications | ||
Parameters | — | 1T |
Context window | — | 128k |
| Benchmarks | ||
Nonsense detection BullshitBench v2Given a confidently-worded but nonsensical prompt, does the AI spot that it makes no sense and push back — instead of playing along and inventing an answer? The score is how often it clearly called out the nonsense. Higher is better. | — | 10% |
Agentic coding SWE-Bench ProCan the AI fix real bugs in real software? It's handed actual problems from open-source projects and has to write code that genuinely solves them. Higher is better. | 63.2% | — |
Coding SWE-Bench VerifiedReal coding tasks pulled from open-source projects — the AI has to find and fix actual bugs. A human-checked version of the original SWE-Bench. Higher is better. | — | 65.8% |
Agentic coding CursorBench v3.1Cursor's own test of harder, real-world coding tasks inside a code editor. Higher is better. | 61.2% | — |
Agentic terminal coding Terminal-Bench 2.1Can the AI work in a command-line terminal — running commands and finishing technical setup tasks the way a developer would? Higher is better. | 80.4% | — |
Multidisciplinary reasoning Humanity's Last Exam · no toolsHumanity's Last Exam — extremely hard expert questions across many subjects, written so you can't just look up the answer. “No tools” means the AI answers on its own. Higher is better. | 43.2% | — |
Multidisciplinary reasoning Humanity's Last Exam · with toolsHumanity's Last Exam — extremely hard expert questions across many subjects. “With tools” means the AI is allowed to search the web or run code while answering. Higher is better. | 57.4% | — |
Science GPQA DiamondGraduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | — | 75.1% |
Agentic computer use OSWorld-VerifiedCan the AI actually operate a computer — clicking, typing, and using real apps — to finish tasks on its own? Higher is better. | 81.2% | — |
Knowledge work GDPval-AAMeasures how well the AI does economically valuable knowledge work, judged against human experts. Shown as a rating (like a chess Elo) — higher is better. | 1618 | — |
| Timeline | ||
| Release gap | Kimi K2 shipped 354 days before Claude Sonnet 5 | |
Which is better: Claude Sonnet 5 or Kimi K2?
Claude Sonnet 5 and Kimi K2 don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Kimi K2 shipped 354 days before Claude Sonnet 5, so benchmark comparisons should account for the intervening progress.
Claude Sonnet 5 is proprietary, while Kimi K2 is open weight.
Direct benchmark comparisons are unavailable — Claude Sonnet 5 and Kimi K2 don't publish scores on any of the same benchmarks.
Frequently asked questions
Claude Sonnet 5 was released by Anthropic on Jun 30 2026.
Kimi K2 was released by Moonshot AI on Jul 11 2025.
Claude Sonnet 5 is a proprietary model released by Anthropic. Kimi K2 is an open weight model released by Moonshot AI.
Other comparisons
Claude Sonnet 5 vs GPT-5.6 SolKimi K2 vs GPT-5.6 SolClaude Sonnet 5 vs Gemini OmniKimi K2 vs Gemini OmniClaude Sonnet 5 vs Muse SparkKimi K2 vs Muse SparkClaude Sonnet 5 vs Grok 4.3 BetaKimi K2 vs Grok 4.3 BetaClaude Sonnet 5 vs DeepSeek-V4-ProKimi K2 vs DeepSeek-V4-ProClaude Sonnet 5 vs Mistral Medium 3.5Kimi K2 vs Mistral Medium 3.5