Claude Opus 4 vs gpt-oss-20b
Anthropic Claude Opus 4 | OpenAI gpt-oss-20b | |
|---|---|---|
| Overview | ||
| Company | Anthropic | OpenAI |
| Release date | May 22 2025 | 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. | 34% | — |
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. | 72.5% | — |
Science GPQA DiamondGraduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | 79.6% | — |
| Timeline | ||
| Release gap | Claude Opus 4 shipped 75 days before gpt-oss-20b | |
Which is better: Claude Opus 4 or gpt-oss-20b?
Claude Opus 4 and gpt-oss-20b don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. Claude Opus 4 shipped 75 days before gpt-oss-20b, so benchmark comparisons should account for the intervening progress.
Claude Opus 4 is proprietary, while gpt-oss-20b is open weight.
Direct benchmark comparisons are unavailable — Claude Opus 4 and gpt-oss-20b don't publish scores on any of the same benchmarks.
Frequently asked questions
Claude Opus 4 was released by Anthropic on May 22 2025.
gpt-oss-20b was released by OpenAI on Aug 5 2025.
Claude Opus 4 is a proprietary model released by Anthropic. gpt-oss-20b is an open weight model released by OpenAI.
Other comparisons
Claude Opus 4 vs Gemini Omnigpt-oss-20b vs Gemini OmniClaude Opus 4 vs Muse Spark 1.1gpt-oss-20b vs Muse Spark 1.1Claude Opus 4 vs Grok 4.5gpt-oss-20b vs Grok 4.5Claude Opus 4 vs DeepSeek-V4-Progpt-oss-20b vs DeepSeek-V4-ProClaude Opus 4 vs Mistral Medium 3.5gpt-oss-20b vs Mistral Medium 3.5Claude Opus 4 vs Kimi K2.7 Codegpt-oss-20b vs Kimi K2.7 Code