Claude Opus 4.6 vs gpt-oss-120b
Anthropic Claude Opus 4.6 | OpenAI gpt-oss-120b | |
|---|---|---|
| Overview | ||
| Company | Anthropic | OpenAI |
| Release date | Feb 5 2026 | Aug 5 2025 |
| Access | Proprietary | Open Weight |
| 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. | 87%Best | 11% |
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. | 80.8% | — |
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. | 75% | — |
Web browsing BrowseCompCan the AI browse the web and track down hard-to-find answers? Higher is better. | 83.7% | — |
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. | 53% | — |
Science GPQA DiamondGraduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | 91.3% | — |
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. | 1504 | — |
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. | 1543 | — |
| Timeline | ||
| Release gap | gpt-oss-120b shipped 184 days before Claude Opus 4.6 | |
Which is better: Claude Opus 4.6 or gpt-oss-120b?
Claude Opus 4.6 leads gpt-oss-120b on 1 of the 1 benchmark they both report (BullshitBench v2). gpt-oss-120b shipped 184 days before Claude Opus 4.6, so benchmark comparisons should account for the intervening progress.
Claude Opus 4.6 is proprietary, while gpt-oss-120b is open weight.
On BullshitBench v2, Claude Opus 4.6 leads at 87% vs gpt-oss-120b at 11%.
Frequently asked questions
Claude Opus 4.6 was released by Anthropic on Feb 5 2026.
gpt-oss-120b was released by OpenAI on Aug 5 2025.
Claude Opus 4.6 is a proprietary model released by Anthropic. gpt-oss-120b is an open weight model released by OpenAI.
Other comparisons
Claude Opus 4.6 vs Gemini Omnigpt-oss-120b vs Gemini OmniClaude Opus 4.6 vs Muse Spark 1.1gpt-oss-120b vs Muse Spark 1.1Claude Opus 4.6 vs Grok 4.5gpt-oss-120b vs Grok 4.5Claude Opus 4.6 vs DeepSeek-V4-Progpt-oss-120b vs DeepSeek-V4-ProClaude Opus 4.6 vs Mistral Medium 3.5gpt-oss-120b vs Mistral Medium 3.5Claude Opus 4.6 vs Kimi K2.7 Codegpt-oss-120b vs Kimi K2.7 Code