gpt-oss-120bvsGrok 4.20 Beta
gpt-oss-120b | Grok 4.20 Beta | |
|---|---|---|
| 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. | 11% | 56%Best |
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% |
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 | OpenAI | SpaceXAI |
| Release date | Aug 5 2025 | Feb 17 2026 |
| Access | Open Weight | Proprietary |
Which is better: gpt-oss-120b or Grok 4.20 Beta?
Grok 4.20 Beta leads gpt-oss-120b on 1 of the 1 benchmark they both report (BullshitBench v2). gpt-oss-120b shipped 196 days before Grok 4.20 Beta, so benchmark comparisons should account for the intervening progress.
gpt-oss-120b is open weight, while Grok 4.20 Beta is proprietary.
On BullshitBench v2, Grok 4.20 Beta leads at 56% vs gpt-oss-120b at 11%.
Frequently asked questions
gpt-oss-120b was released by OpenAI on Aug 5 2025.
Grok 4.20 Beta was released by SpaceXAI on Feb 17 2026.
gpt-oss-120b is an open weight model released by OpenAI. Grok 4.20 Beta is a proprietary model released by SpaceXAI.
Other comparisons
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