GPT-5.5 vs Kimi K2.5
Head to head on 28 shared benchmarks, with price, context window, and release dates.
Benchmark scores
61evals · sort by any column, ⤢ to expand fullscreen
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| GPT-5.5 OpenAI | 68.4% | 86.0% | 1844elo | 78.2 | 51.8% | 51.7% | 76.8% | 13.7% | 46.1% | 84.7% | 82.5% | 81.1% | 73.0% | 87.7% | 96.3% | 87.7% | 92.8% | 49.1% | 86.9% | 68.8% | 78.7% | 51.5% | 47.3% | 75.0% | 49.2% | 57.4% | 69.8% | 69.3% | - | 86.2% | 54.2% | 12.9% | 36.2% | 90.0% | 100.0% | 1315elo | 34.0% | 5.7% | 44.8% | 24.9% | 1769elo | 15.1% | 51.8% | - | - | - | 2.1% | - | 88.6% | 45.3% | 100.0% | 50.0% | 4.2 | - | - | - | 58.6% | 75.7% | 83.4% | - | 68.1% | 61.9% |
| Kimi K2.5 Moonshot AI | 68.3% | 39.0% | 1576elo | 74.9 | 35.8% | 27.9% | 78.9% | 13.2% | 43.7% | 72.5% | 77.9% | 61.4% | 57.4% | 77.7% | 84.9% | 76.0% | 62.0% | 39.3% | 76.4% | 66.5% | 63.3% | 49.9% | 39.6% | 74.2% | 18.9% | 26.3% | 17.5% | 81.3% | 96.1 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 95.4 | 78.5% | 10421 | - | 87.1 | - | - | - | - | - | 73 | 67.3% | 70.8% | - | - | - | 69.4 | - | 56.8% |
2 / 2 models
| Attribute | GPT-5.5 OpenAI | Kimi K2.5 Moonshot AI |
|---|---|---|
| Description | GPT-5.5 is an AI model from OpenAI. | Kimi K2.5 is an AI model from Kimi. |
| Family | GPT | Kimi |
| Params | - | - |
| Open weights | closed | closed |
| License | proprietary | Modified MIT |
| Released | 23 Apr 2026 | 27 Jan 2026 |
| Context | 1,050,000 | 262,144 |
| Input $/1M | $5.00 | $0.60 |
| Output $/1M | $30.00 | $3.00 |
| Cache read $/1M | $0.500 | $0.100 |
| Cache write $/1M | - | - |
| Speed | 0 tok/s | 0 tok/s |
| Latency | 0.00 s | 0.00 s |
| Modalities | file, image, text | text, image |
| Providers | - | - |
| Publisher | OpenAI | Moonshot AI |
| Reported scores | 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) | GPQA Diamond78.9% (AA) Humanity's Last Exam (HLE)13.2% (AA) IFBench43.7% (AA) SciCode39.6% (AA) τ²-bench (Tau²-bench)81.3% (AA) |
FAQ
- Is GPT-5.5 or Kimi K2.5 better?
- Across the 28 benchmarks both models report on Sophon, GPT-5.5 leads on 26 of them. Which one is "better" depends on the benchmark - the table above shows every shared score.
- How do GPT-5.5 and Kimi K2.5 compare on GPQA Diamond?
- GPT-5.5 scores 76.8% and Kimi K2.5 scores 78.9% on GPQA Diamond.
- Which is cheaper, GPT-5.5 or Kimi K2.5?
- Kimi K2.5 is cheaper at $3.00 per million output tokens against $30.00 for GPT-5.5 - about 10.0x.
- When were GPT-5.5 and Kimi K2.5 released?
- GPT-5.5 was released 23 Apr 2026 by OpenAI. Kimi K2.5 was released 27 Jan 2026 by Moonshot AI.
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