Claude Opus 4.5 vs gpt-oss-120b
Head to head on 21 shared benchmarks, with price, context window, and release dates.
Benchmark scores
51evals · sort by any column, ⤢ to expand fullscreen
| Model | ||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Claude Opus 4.5 Anthropic | 91.3% | 61.3% | 1687elo | 73.1 | 86.6% | 30.1% | 58.0% | 78.1% | 79.7% | 74.4% | 62.5% | 81.3% | 90.4% | 80.1% | 87.1% | 89.5% | 49.5% | 79.2% | 74.3% | 47.0% | 89.5% | - | - | - | 16.7% | - | 35.6% | 6.1% | 20.7% | 84.7% | 12.13 | - | 83.8% | 83.5% | - | - | 45.2% | 83.2% | - | 68.7% | 100.0% | 37.4 | 36.0% | 77.5% | 45.0% | 45.3 | - | 70.7% | 61.8 | - | 20.6% | 64.8% |
| gpt-oss-120b OpenAI | 93.4% | 58.2% | 961elo | 35.8 | 78.2% | 19.6% | 69.0% | 51.0% | 60.2% | 38.8% | 50.3% | 48.6% | 68.9% | 39.2% | 87.8% | 80.8% | 34.0% | 26.0% | 71.6% | 23.5% | 65.8% | 41.8% | 38.9% | 7.6% | - | 11.0% | - | - | - | - | - | 57.6 | - | - | 1.62 | 1.53 | - | - | 80.0% | - | - | - | - | - | - | - | 97.9% | - | - | 65.6% | - | 54.1% |
2 / 2 models
| Attribute | Claude Opus 4.5 Anthropic | gpt-oss-120b OpenAI |
|---|---|---|
| Description | Claude Opus 4.5 is an AI model from Anthropic. | GPT-Oss 120b is an AI model from OpenAI, released with open weights. |
| Family | Claude | GPT |
| Params | - | - |
| Open weights | closed | open |
| License | proprietary | apache-2.0 |
| Released | 24 Nov 2025 | 5 Aug 2025 |
| Context | 200,000 | 131,072 |
| Input $/1M | $5.00 | $0.15 |
| Output $/1M | $25.00 | $0.59 |
| Cache read $/1M | $0.500 | $0.075 |
| Cache write $/1M | $6.250 | - |
| Speed | 0 tok/s | 209 tok/s |
| Latency | 0.00 s | 0.51 s |
| Modalities | file, image, text | text |
| Providers | - | - |
| Publisher | Anthropic | OpenAI |
| Reported scores | GPQA Diamond78.2% (AA) Humanity's Last Exam (HLE)19.6% (AA) LiveCodeBench87.8% (AA) MMLU-Pro80.8% (AA) SciCode34.0% (AA) |
FAQ
- Is Claude Opus 4.5 or gpt-oss-120b better?
- Across the 21 benchmarks both models report on Sophon, Claude Opus 4.5 leads on 18 of them. Which one is "better" depends on the benchmark - the table above shows every shared score.
- How do Claude Opus 4.5 and gpt-oss-120b compare on GPQA Diamond?
- Claude Opus 4.5 scores 86.6% and gpt-oss-120b scores 78.2% on GPQA Diamond.
- Which is cheaper, Claude Opus 4.5 or gpt-oss-120b?
- gpt-oss-120b is cheaper at $0.59 per million output tokens against $25.00 for Claude Opus 4.5 - about 42.4x.
- When were Claude Opus 4.5 and gpt-oss-120b released?
- Claude Opus 4.5 was released 24 Nov 2025 by Anthropic. gpt-oss-120b was released 5 Aug 2025 by OpenAI.
Other head-to-heads
56Claude Opus 4.5 vs GPT-5.235 shared evalsClaude Opus 4.5 vs Claude Sonnet 4.534 shared evalsClaude Opus 4.5 vs GPT-5 Mini31 shared evalsClaude Opus 4.5 vs Grok 4.1 Fast29 shared evalsClaude Opus 4.5 vs Gemini 3.1 Pro Preview28 shared evalsClaude Opus 4.5 vs Claude Opus 4.628 shared evalsClaude Opus 4.5 vs GPT-5.428 shared evalsClaude Opus 4.5 vs DeepSeek V3.227 shared evalsClaude Opus 4.5 vs GPT-5 Nano26 shared evalsClaude 4 Sonnet vs Claude Opus 4.526 shared evalsClaude Opus 4.5 vs Kimi K2.526 shared evalsGPT-5 Mini vs gpt-oss-120b25 shared evalsClaude Opus 4.5 vs GPT-5.525 shared evalsClaude Opus 4.5 vs GLM 4.725 shared evalsClaude Opus 4.5 vs GPT-5.4 Mini25 shared evalsClaude Opus 4.5 vs Claude Opus 4.824 shared evalsClaude Opus 4.5 vs Claude Opus 4.724 shared evalsClaude Opus 4.5 vs Gemini 2.5 Pro24 shared evalsClaude Sonnet 4.5 vs gpt-oss-120b23 shared evalsClaude Opus 4.5 vs GPT-523 shared evalsClaude Fable 5 vs Claude Opus 4.523 shared evalsClaude Opus 4.5 vs Claude Sonnet 4.623 shared evalsClaude Opus 4.5 vs GLM 5.123 shared evalsDeepSeek V3.2 vs gpt-oss-120b23 shared evalsGPT-5 Nano vs gpt-oss-120b22 shared evalsGPT-5.2 vs gpt-oss-120b22 shared evalsClaude Opus 4.5 vs Qwen3.6 Plus22 shared evalsClaude 4 Sonnet vs gpt-oss-120b21 shared evalsgpt-oss-120b vs Grok 4.1 Fast20 shared evalsGLM 4.7 vs gpt-oss-120b20 shared evalsGPT-5.5 vs gpt-oss-120b19 shared evalsClaude Opus 4.6 vs gpt-oss-120b19 shared evalsgpt-oss-120b vs Kimi K2.519 shared evalsGLM 5.1 vs gpt-oss-120b19 shared evalsGemini 2.5 Pro vs gpt-oss-120b19 shared evalsGemini 3.1 Pro Preview vs gpt-oss-120b18 shared evalsClaude Opus 4.8 vs gpt-oss-120b18 shared evalsClaude Opus 4.5 vs GPT-4o18 shared evalsClaude Fable 5 vs gpt-oss-120b18 shared evalsGPT-5.4 vs gpt-oss-120b18 shared evalsClaude Sonnet 4.6 vs gpt-oss-120b18 shared evalsClaude Opus 4.7 vs gpt-oss-120b18 shared evalsGPT-5 vs gpt-oss-120b17 shared evalsGPT-4o vs gpt-oss-120b17 shared evalsGPT-5.4 Mini vs gpt-oss-120b17 shared evalsClaude Opus 4.5 vs GPT-4.1 Mini16 shared evalsClaude Opus 4.5 vs GPT-4.116 shared evalsGPT-4.1 vs gpt-oss-120b16 shared evalsgpt-oss-120b vs Qwen3.6 Plus16 shared evalsGPT-4.1 Mini vs gpt-oss-120b15 shared evalsClaude Opus 4.5 vs GPT-4o-mini15 shared evalsClaude Opus 4.5 vs GPT-4.1 Nano15 shared evalsGPT-4o-mini vs gpt-oss-120b15 shared evalsGPT-4.1 Nano vs gpt-oss-120b14 shared evalsClaude Opus 4.5 vs GPT-6 Astra11 shared evalsGPT-6 Astra vs gpt-oss-120b6 shared evals
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