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% | 83.0% | 1844elo | 78.2 | 51.8% | 51.7% | 93.5% | 45.8% | 75.9% | 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% | 55.8% | 75.0% | 60.6% | 57.4% | 69.8% | 93.9% | - | 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% | 64.5% |
| Kimi K2.5 Moonshot AI | 68.3% | 35.0% | 1579elo | 74.9 | 35.8% | 27.9% | 87.9% | 30.7% | 70.2% | 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% | 49.0% | 74.2% | 34.8% | 26.3% | 17.5% | 95.9% | 96.1 | - | - | - | - | - | - | - | - | - | - | - | - | - | - | 95.4 | 78.5% | 10421 | - | 87.1 | - | - | - | - | - | 73 | 67.3% | 70.8% | - | - | - | 69.4 | - | 59.8% |
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 | open |
| 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 | $2.75 |
| Cache read $/1M | $0.500 | $0.070 |
| 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 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 Diamond87.9% (AA) Humanity's Last Exam (HLE)30.7% (AA) IFBench70.2% (AA) SciCode49.0% (AA) τ²-bench (Tau²-bench)95.9% (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 27 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 93.5% and Kimi K2.5 scores 87.9% on GPQA Diamond.
- Which is cheaper, GPT-5.5 or Kimi K2.5?
- Kimi K2.5 is cheaper at $2.75 per million output tokens against $30.00 for GPT-5.5 - about 10.9x.
- 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.
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 Opus 4.6 vs Kimi K2.531 shared evalsClaude Sonnet 4.6 vs GPT-5.530 shared evalsGemini 3.1 Pro Preview vs Kimi K2.530 shared evalsGPT-5.2 vs Kimi K2.529 shared evalsKimi K2.5 vs Qwen3.6 Plus29 shared evalsClaude Sonnet 4.5 vs Kimi K2.528 shared evalsClaude Opus 4.6 vs GPT-5.528 shared evalsGPT-5.4 vs GPT-5.528 shared evalsClaude Opus 4.8 vs Kimi K2.528 shared evalsGPT-5.4 vs Kimi K2.528 shared evalsClaude Opus 4.7 vs Kimi K2.528 shared evalsGPT-5.2 vs GPT-5.527 shared evalsClaude Sonnet 4.6 vs Kimi K2.527 shared evalsClaude Sonnet 4.5 vs GPT-5.526 shared evalsGPT-5.4 Mini vs GPT-5.526 shared evalsClaude Opus 4.5 vs Kimi K2.526 shared evalsClaude Fable 5 vs Kimi K2.526 shared evalsGLM 5.1 vs Kimi K2.526 shared evalsGPT-5 Mini vs GPT-5.525 shared evalsGPT-5 Mini vs Kimi K2.525 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 evalsDeepSeek V3.2 vs Kimi K2.525 shared evalsGPT-5.4 Mini vs Kimi K2.525 shared evalsGrok 4.1 Fast vs Kimi K2.524 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 evalsClaude 4 Sonnet vs Kimi K2.523 shared evalsGemini 2.5 Pro vs GPT-5.522 shared evalsGLM 4.7 vs GPT-5.522 shared evalsGPT-5 Nano vs Kimi K2.522 shared evalsGemini 2.5 Pro vs Kimi K2.521 shared evalsGLM 4.7 vs Kimi K2.520 shared evalsGPT-5.5 vs GPT-6 Astra19 shared evalsGPT-5.5 vs gpt-oss-120b19 shared evalsgpt-oss-120b vs Kimi K2.519 shared evalsGPT-5 vs GPT-5.518 shared evalsGPT-5 vs Kimi K2.518 shared evalsGPT-4o vs GPT-5.515 shared evalsGPT-4o vs Kimi K2.515 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-6 Astra vs Kimi K2.513 shared evalsGPT-4.1 Mini vs Kimi K2.512 shared evalsGPT-4.1 vs GPT-5.512 shared evalsGPT-4.1 vs Kimi K2.512 shared evalsGPT-4o-mini vs Kimi K2.512 shared evalsGPT-4.1 Nano vs Kimi K2.512 shared evals
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