GPT-4o vs GPT-5.5
Head to head on 15 shared benchmarks, with price, context window, and release dates.
Benchmark scores
70evals · sort by any column, ⤢ to expand fullscreen
| Model | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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| GPT-5.5 OpenAI | 68.4% | 51.7% | 76.8% | 13.7% | 46.1% | 84.7% | 82.5% | 73.0% | 87.7% | 88.6% | 68.8% | 47.3% | 75.0% | 49.2% | 69.3% | - | - | - | - | 86.2% | 54.2% | 12.9% | - | 36.2% | - | 86.0% | 90.0% | 100.0% | - | 1315elo | 1844elo | 78.2 | 34.0% | 51.8% | 5.7% | 44.8% | 24.9% | 1769elo | 15.1% | - | 51.8% | 2.1% | - | 81.1% | 96.3% | 87.7% | - | - | 92.8% | 49.1% | - | 86.9% | 78.7% | - | 45.3% | 100.0% | 50.0% | 51.5% | - | 4.2 | - | 58.6% | - | 75.7% | 83.4% | - | 57.4% | 68.1% | 69.8% | - | 61.9% |
| GPT-4o OpenAI | 45.9% | 0.3% | 54.3% | 2.4% | 34.3% | 55.1% | 46.1% | 70.1% | 49.0% | 74.8% | 57.4% | 33.3% | 74.5% | 8.3% | 25.1% | 18.2% | 15.0% | 6.0% | 38 | - | - | - | 0.0% | - | 0.33 | - | - | - | 6.1% | - | - | - | - | - | - | - | - | - | - | 96.1 | - | - | 0.0% | - | - | - | 30.9% | 75.9% | - | - | 10.8% | - | - | 54.0% | - | - | - | - | 5.71 | - | 21.6% | - | 61.2 | - | - | 0.98 | - | - | - | 32.5% | 33.4% |
2 / 2 models
| Attribute | GPT-4o OpenAI | GPT-5.5 OpenAI |
|---|---|---|
| Description | GPT-4o is an AI model from OpenAI. | GPT-5.5 is an AI model from OpenAI. |
| Family | GPT | GPT |
| Params | - | - |
| Open weights | closed | closed |
| License | proprietary | proprietary |
| Released | 20 Nov 2024 | 23 Apr 2026 |
| Context | 128,000 | 1,050,000 |
| Input $/1M | $2.50 | $5.00 |
| Output $/1M | $10.00 | $30.00 |
| Cache read $/1M | $1.250 | $0.500 |
| Cache write $/1M | - | - |
| Speed | 0 tok/s | 0 tok/s |
| Latency | 0.00 s | 0.00 s |
| Modalities | text, image, file | file, image, text |
| Providers | - | - |
| Publisher | OpenAI | OpenAI |
| Reported scores | Taubench61.2 pass^1 GSM8K96.1 Accuracy ScholarSearch5.71 Social Sciences & Humanities (%) MortgageTax57.4% AIME202438 pass@1 | GPQA Diamond76.8% (AA) Humanity's Last Exam (HLE)13.7% (AA) IFBench46.1% (AA) SciCode47.3% (AA) τ²-bench (Tau²-bench)69.3% (AA) |
FAQ
- Is GPT-4o or GPT-5.5 better?
- Across the 15 benchmarks both models report on Sophon, GPT-5.5 leads on 15 of them. Which one is "better" depends on the benchmark - the table above shows every shared score.
- How do GPT-4o and GPT-5.5 compare on GPQA Diamond?
- GPT-4o scores 54.3% and GPT-5.5 scores 76.8% on GPQA Diamond.
- Which is cheaper, GPT-4o or GPT-5.5?
- GPT-4o is cheaper at $10.00 per million output tokens against $30.00 for GPT-5.5 - about 3.0x.
- When were GPT-4o and GPT-5.5 released?
- GPT-4o was released 20 Nov 2024 by OpenAI. GPT-5.5 was released 23 Apr 2026 by OpenAI.
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