GPT-5.5 vs gpt-oss-120b
Head to head on 19 shared benchmarks, with price, context window, and release dates.
Benchmark scores
64evals · sort by any column, ⤢ to expand fullscreen
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| GPT-5.5 OpenAI | 68.4% | 83.0% | 1844elo | 78.2 | 93.5% | 45.8% | 75.9% | 84.7% | 82.5% | 81.1% | 73.0% | 87.7% | 96.3% | 87.7% | 88.6% | 55.8% | 75.0% | 60.6% | 93.9% | - | - | 86.2% | 54.2% | 12.9% | - | - | 36.2% | 90.0% | 100.0% | 1315elo | 34.0% | 51.8% | 5.7% | 51.7% | 44.8% | 24.9% | 1769elo | 15.1% | - | 51.8% | 2.1% | - | - | - | 92.8% | 49.1% | 86.9% | - | 68.8% | 78.7% | 45.3% | 100.0% | 50.0% | 51.5% | 4.2 | - | - | 58.6% | 75.7% | 83.4% | - | 57.4% | 68.1% | 69.8% | 64.5% |
| gpt-oss-120b OpenAI | 58.2% | 11.0% | 961elo | 35.8 | 78.2% | 19.6% | 69.0% | 51.0% | 60.2% | 38.8% | 50.3% | 48.6% | 68.9% | 39.2% | 80.8% | 34.0% | 71.6% | 23.5% | 65.8% | 41.8% | 93.4% | - | - | - | 38.9% | 7.6% | - | - | - | - | - | - | - | - | - | - | - | - | 57.6 | - | - | 87.8% | 1.62 | 1.53 | - | - | - | 80.0% | - | - | - | - | - | - | - | 97.9% | 26.0% | - | - | - | 65.6% | - | - | - | 54.1% |
2 / 2 models
| Attribute | GPT-5.5 OpenAI | gpt-oss-120b OpenAI |
|---|---|---|
| Description | GPT-5.5 is an AI model from OpenAI. | GPT-Oss 120b is an AI model from OpenAI, released with open weights. |
| Family | GPT | GPT |
| Params | - | - |
| Open weights | closed | open |
| License | proprietary | apache-2.0 |
| Released | 23 Apr 2026 | 5 Aug 2025 |
| Context | 1,050,000 | 131,072 |
| Input $/1M | $5.00 | $0.15 |
| Output $/1M | $30.00 | $0.59 |
| Cache read $/1M | $0.500 | $0.075 |
| Cache write $/1M | - | - |
| Speed | 0 tok/s | 209 tok/s |
| Latency | 0.00 s | 0.51 s |
| Modalities | file, image, text | text |
| Providers | - | - |
| Publisher | OpenAI | OpenAI |
| Reported scores | GPQA Diamond93.5% (AA) Humanity's Last Exam (HLE)45.8% (AA) IFBench75.9% (AA) SciCode55.8% (AA) τ²-bench (Tau²-bench)93.9% (AA) | GPQA Diamond78.2% (AA) Humanity's Last Exam (HLE)19.6% (AA) LiveCodeBench87.8% (AA) MMLU-Pro80.8% (AA) SciCode34.0% (AA) |
FAQ
- Is GPT-5.5 or gpt-oss-120b better?
- Across the 19 benchmarks both models report on Sophon, GPT-5.5 leads on 19 of them. Which one is "better" depends on the benchmark - the table above shows every shared score.
- How do GPT-5.5 and gpt-oss-120b compare on GPQA Diamond?
- GPT-5.5 scores 93.5% and gpt-oss-120b scores 78.2% on GPQA Diamond.
- Which is cheaper, GPT-5.5 or gpt-oss-120b?
- gpt-oss-120b is cheaper at $0.59 per million output tokens against $30.00 for GPT-5.5 - about 50.8x.
- When were GPT-5.5 and gpt-oss-120b released?
- GPT-5.5 was released 23 Apr 2026 by OpenAI. gpt-oss-120b was released 5 Aug 2025 by OpenAI.
Other head-to-heads
56Gemini 3.1 Pro Preview vs GPT-5.541 shared evalsClaude Opus 4.8 vs GPT-5.541 shared evalsClaude Fable 5 vs GPT-5.539 shared evalsClaude Opus 4.7 vs GPT-5.532 shared evalsGLM 5.1 vs GPT-5.531 shared evalsClaude Sonnet 4.6 vs GPT-5.530 shared evalsClaude Opus 4.6 vs GPT-5.528 shared evalsGPT-5.4 vs GPT-5.528 shared evalsGPT-5.5 vs Kimi K2.528 shared evalsGPT-5.2 vs GPT-5.527 shared evalsClaude Sonnet 4.5 vs GPT-5.526 shared evalsGPT-5.4 Mini vs GPT-5.526 shared evalsGPT-5 Mini vs GPT-5.525 shared evalsGPT-5 Mini vs gpt-oss-120b25 shared evalsClaude Opus 4.5 vs GPT-5.525 shared evalsGPT-5.5 vs Qwen3.6 Plus25 shared evalsGPT-5.5 vs Grok 4.1 Fast25 shared evalsClaude Sonnet 4.5 vs gpt-oss-120b23 shared evalsGPT-5 Nano vs GPT-5.523 shared evalsClaude 4 Sonnet vs GPT-5.523 shared evalsDeepSeek V3.2 vs GPT-5.523 shared evalsDeepSeek V3.2 vs gpt-oss-120b23 shared evalsGemini 2.5 Pro vs GPT-5.522 shared evalsGLM 4.7 vs GPT-5.522 shared evalsGPT-5 Nano vs gpt-oss-120b22 shared evalsGPT-5.2 vs gpt-oss-120b22 shared evalsClaude Opus 4.5 vs gpt-oss-120b21 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-6 Astra19 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 evalsGPT-5 vs GPT-5.518 shared evalsGemini 3.1 Pro Preview vs gpt-oss-120b18 shared evalsClaude Opus 4.8 vs gpt-oss-120b18 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 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 evalsGPT-4o vs GPT-5.515 shared evalsGPT-4o-mini vs gpt-oss-120b15 shared evalsGPT-4.1 Nano vs gpt-oss-120b14 shared evalsGPT-4.1 Mini vs GPT-5.513 shared evalsGPT-4o-mini vs GPT-5.513 shared evalsGPT-4.1 Nano vs GPT-5.513 shared evalsGPT-4.1 vs GPT-5.512 shared evalsGPT-6 Astra vs gpt-oss-120b6 shared evals
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