Claude 3 OpusvsKimi K2.6
Claude 3 Opus | Kimi K2.6 | |
|---|---|---|
| Specifications | ||
Parameters | — | 1T |
Context window | — | 256k |
| 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. | — | 65% |
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. | 33% | 80.2%Best |
Agentic coding CursorBench v3.1Cursor's own test of harder, real-world coding tasks inside a code editor. Higher is better. | — | 47.6% |
Next.js coding Next.js EvalsVercel's open eval of how well AI coding agents build and migrate real Next.js apps — measured as the share of tasks the agent completes successfully. Higher is better. | — | 67% |
Competitive coding LiveCodeBenchCoding problems published so recently the AI can't have seen them in training — a contamination-free test of raw programming skill. Higher is better. | — | 89.6% |
Science GPQA DiamondGraduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | 50.4% | 90.5%Best |
Community preference Arena Elo (Text)Real people chat with two anonymous AIs side by side and vote for the answer they prefer. Votes become a chess-style Elo rating on arena.ai — it measures which AI people actually like, not test scores. Higher is better. | — | 1461 |
Community preference (code) Arena Elo (Code)Like the text arena, but people vote on which AI writes better code. The votes become a chess-style Elo rating on arena.ai. Higher is better. | — | 1513 |
| Overview | ||
| Company | Anthropic | Moonshot AI |
| Release date | Mar 4 2024 | Apr 21 2026 |
| Access | Proprietary | Open Weight |
Which is better: Claude 3 Opus or Kimi K2.6?
Kimi K2.6 leads Claude 3 Opus on 2 of the 2 benchmarks they both report (SWE-Bench Verified, GPQA Diamond). Claude 3 Opus shipped 778 days before Kimi K2.6, so benchmark comparisons should account for the intervening progress.
Claude 3 Opus is proprietary, while Kimi K2.6 is open weight.
On SWE-Bench Verified, Kimi K2.6 leads at 80.2% vs Claude 3 Opus at 33%. On GPQA Diamond, Kimi K2.6 leads at 90.5% vs Claude 3 Opus at 50.4%.
Frequently asked questions
Claude 3 Opus was released by Anthropic on Mar 4 2024.
Kimi K2.6 was released by Moonshot AI on Apr 21 2026.
Kimi K2.6 leads on SWE-Bench Verified — Claude 3 Opus 33% vs Kimi K2.6 80.2%.
Kimi K2.6 leads on GPQA Diamond — Claude 3 Opus 50.4% vs Kimi K2.6 90.5%.
Claude 3 Opus is a proprietary model released by Anthropic. Kimi K2.6 is an open weight model released by Moonshot AI.