Kimi K2vsGrok 4.20 Beta
Kimi K2 | Grok 4.20 Beta | |
|---|---|---|
| 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% | 56%Best |
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% | — |
Abstract reasoning ARC-AGI-2Puzzle-style tests of abstract reasoning and pattern-finding — the kind of thing people find easy but AIs often struggle with. Higher is better. | — | 53.3% |
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% | — |
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. | — | 1475 |
| Overview | ||
| Company | Moonshot AI | SpaceXAI |
| Release date | Jul 11 2025 | Feb 17 2026 |
| Access | Open Weight | Proprietary |
Which is better: Kimi K2 or Grok 4.20 Beta?
Grok 4.20 Beta leads Kimi K2 on 1 of the 1 benchmark they both report (BullshitBench v2). Kimi K2 shipped 221 days before Grok 4.20 Beta, so benchmark comparisons should account for the intervening progress.
Kimi K2 is open weight, while Grok 4.20 Beta is proprietary.
On BullshitBench v2, Grok 4.20 Beta leads at 56% vs Kimi K2 at 10%.
Frequently asked questions
Kimi K2 was released by Moonshot AI on Jul 11 2025.
Grok 4.20 Beta was released by SpaceXAI on Feb 17 2026.
Kimi K2 is an open weight model released by Moonshot AI. Grok 4.20 Beta is a proprietary model released by SpaceXAI.
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