Claude 1 vs Kimi K2
Anthropic Claude 1 | Moonshot AI Kimi K2 | |
|---|---|---|
| Overview | ||
| Company | Anthropic | Moonshot AI |
| Release date | Mar 14 2023 | 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% |
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% |
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% |
| Timeline | ||
| Release gap | Claude 1 shipped 850 days before Kimi K2 | |
Which is better: Claude 1 or Kimi K2?
Claude 1 and Kimi K2 don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Claude 1 shipped 850 days before Kimi K2, so benchmark comparisons should account for the intervening progress.
Claude 1 is proprietary, while Kimi K2 is open weight.
Direct benchmark comparisons are unavailable — Claude 1 and Kimi K2 don't publish scores on any of the same benchmarks.
Frequently asked questions
Claude 1 was released by Anthropic on Mar 14 2023.
Kimi K2 was released by Moonshot AI on Jul 11 2025.
Claude 1 is a proprietary model released by Anthropic. Kimi K2 is an open weight model released by Moonshot AI.