GPT-5.5 vs Kimi K2.6
GPT-5.5 
Kimi K2.6 Verdict
- GPT-5.5 leads on quality: 66.7 vs 60.7.
- GPT-5.5 is stronger in agents & tools, composite, human preference, knowledge, long context, multimodal, reasoning.
- Kimi K2.6 is stronger in coding, instruction following, maths.
- Kimi K2.6 is 6.6× cheaper ($1.71 vs $11.25 per 1M blended).
- GPT-5.5 streams 1.9× faster (85 vs 44 tokens per second).
| Metric | GPT-5.5 | Kimi K2.6 |
|---|---|---|
| BenchLeader Index | 66.7 | 60.7 |
| Agents & tools score | 68.5 | 45.1 |
| Coding score | 57.2 | 60.4 |
| Composite score | 77.8 | 68.6 |
| Human preference score | 67.9 | 60.8 |
| Instruction following score | 73.6 | 73.7 |
| Knowledge score | 73.9 | 58.6 |
| Long context score | 68.8 | 67.1 |
| Multimodal score | 64.9 | 63.7 |
| Reasoning score | 70.1 | 66.0 |
| Maths score | – | 53.8 |
| Blended price $/M | $11.25 | $1.71 |
| Output speed | 85 tok/s | 44 tok/s |
| Time to first answer | 58.6 s | 103.2 s |
| Context window | 1.1M | 262k |
| GPQA Diamond | – | 90.8% |
| FrontierMath Tiers 1–3 | – | 57.2% |
| FrontierMath Tier 4 | – | 25.6% |
| OTIS Mock AIME | – | 96.1% |
| SWE-bench Verified (Epoch) | – | 76.7% |
| SimpleQA Verified | – | 34.9% |
| Terminal-Bench | 84.7% | – |
| SimpleBench | 69.0% | – |
| OSWorld-Verified 2.0 | – | 4.6% |
| SciCode | – | 53.5% |
| Remote Labor Index | 6.3% | – |
| WeirdML | – | 55.9% |
| APEX-Agents | 38.5% | 18.9% |
| FrontierCode | 43.0% | – |
| ProofBench | – | 16.0% |
| Epoch Capabilities Index | 159.1 | 151.0 |
| LMArena Text | 1477 | 1461 |
| LMArena Hard Prompts | 1498 | 1485 |
| LMArena Coding | 1509 | 1514 |
| LMArena WebDev | 1458 | 1509 |
| LMArena Vision | 1296 | 1281 |
| LMArena Agent | 3 | – |
| AA Intelligence Index | 38.6 | 31.3 |
| IFBench | 75.8% | 76.0% |
| AA-LCR | 84.3% | 81.0% |
| MMMU-Pro | 79.9% | 79.4% |
| AA-Omniscience | 20.5 | 5.3 |
| Terminal-Bench Hard | 60.6% | 43.9% |
| GPQA Diamond (AA) | 93.5% | 91.1% |
| Humanity's Last Exam (AA) | 45.8% | 37.5% |
| SciCode (AA) | 55.8% | 51.5% |
| τ²-Bench Telecom (AA) | 93.9% | 95.9% |
| LiveCodeBench | – | 86.8% |
| MMLU-Pro | – | 87.6% |
| LegalBench | – | 84.7% |
| CorpFin | – | 66.7% |
| TaxEval | – | 74.7% |
| Terminal-Bench 2.1 (Vals) | – | 53.6% |
| SWE-bench (Vals) | – | 76.2% |
| GPQA Diamond (Vals) | – | 89.1% |
| Vals Index | – | 43.5 |
| HiL-Bench | 39.7% | 18.7% |
| EQ-Bench 4 | 1315 | 1202 |
| Kagi LLM Benchmark | 88.8% | – |
Data as of 2026-09-10. Best configuration of each model; every score links to its source on the model pages.
GPT-5.5 vs Kimi K2.6: questions
- Is GPT-5.5 better than Kimi K2.6?
- GPT-5.5 leads on quality: 66.7 vs 60.7. The BenchLeader Index combines every independent quality benchmark; GPT-5.5 is ahead overall as of 2026-09-10, but check the category scores for your use.
- Is GPT-5.5 better than Kimi K2.6 for coding?
- Kimi K2.6 scores higher in coding (60 vs 57 on the category index, where 50 is average).
- Is GPT-5.5 better than Kimi K2.6 for agentic tasks?
- GPT-5.5 scores higher in agentic tasks (69 vs 45 on the category index, where 50 is average).
- Which is cheaper, GPT-5.5 or Kimi K2.6?
- Kimi K2.6 is cheaper: $1.71 against $11.25 per million tokens, blended at three input tokens per output token.
- Which is faster, GPT-5.5 or Kimi K2.6?
- GPT-5.5 streams faster: 85 against 44 output tokens per second.
- Which has the larger context window?
- GPT-5.5 accepts more context: 1.1M against 262k tokens.