GPT-5.5 Instant vs Kimi K2.6
GPT-5.5 Instant 
Kimi K2.6 Verdict
- GPT-5.5 Instant and Kimi K2.6 are level on quality (60.5 vs 60.7).
- GPT-5.5 Instant is stronger in agents & tools, coding, human preference, knowledge.
- Kimi K2.6 is stronger in composite, instruction following, long context, maths, multimodal, reasoning.
- Kimi K2.6 is 6.6× cheaper ($1.71 vs $11.25 per 1M blended).
- GPT-5.5 Instant streams 2.9× faster (129 vs 44 tokens per second).
| Metric | GPT-5.5 Instant | Kimi K2.6 |
|---|---|---|
| BenchLeader Index | 60.5 | 60.7 |
| Agents & tools score | 70.7 | 45.1 |
| Coding score | 61.1 | 60.4 |
| Composite score | 62.9 | 68.6 |
| Human preference score | 67.5 | 60.8 |
| Instruction following score | 69.8 | 73.7 |
| Knowledge score | 69.4 | 58.6 |
| Long context score | 61.4 | 67.1 |
| Maths score | 42.5 | 53.8 |
| Multimodal score | 59.7 | 63.7 |
| Reasoning score | 62.6 | 66.0 |
| Blended price $/M | $11.25 | $1.71 |
| Output speed | 129 tok/s | 44 tok/s |
| Time to first answer | 16.8 s | 103.2 s |
| Context window | 400k | 262k |
| GPQA Diamond | 82.5% | 90.8% |
| FrontierMath Tiers 1–3 | 26.3% | 57.2% |
| FrontierMath Tier 4 | 2.4% | 25.6% |
| OTIS Mock AIME | 68.1% | 96.1% |
| SWE-bench Verified (Epoch) | – | 76.7% |
| SimpleQA Verified | – | 34.9% |
| OSWorld-Verified 2.0 | – | 4.6% |
| SciCode | 48.6% | 53.5% |
| WeirdML | – | 55.9% |
| APEX-Agents | – | 18.9% |
| ProofBench | – | 16.0% |
| Epoch Capabilities Index | 142.5 | 151.0 |
| LMArena Text | 1474 | 1461 |
| LMArena Hard Prompts | 1491 | 1485 |
| LMArena Coding | 1514 | 1514 |
| LMArena WebDev | – | 1509 |
| LMArena Vision | 1251 | 1281 |
| AA Intelligence Index | 26.8 | 31.3 |
| IFBench | 71.5% | 76.0% |
| AA-LCR | 70.0% | 81.0% |
| MMMU-Pro | – | 79.4% |
| AA-Omniscience | 11.2 | 5.3 |
| Terminal-Bench Hard | 42.4% | 43.9% |
| GPQA Diamond (AA) | 84.7% | 91.1% |
| Humanity's Last Exam (AA) | 21.6% | 37.5% |
| SciCode (AA) | 52.5% | 51.5% |
| τ²-Bench Telecom (AA) | 49.4% | 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 | – | 18.7% |
| EQ-Bench 4 | – | 1202 |
Data as of 2026-09-10. Best configuration of each model; every score links to its source on the model pages.
GPT-5.5 Instant vs Kimi K2.6: questions
- Is GPT-5.5 Instant better than Kimi K2.6?
- GPT-5.5 Instant and Kimi K2.6 are level on quality (60.5 vs 60.7). The BenchLeader Index combines every independent quality benchmark; Kimi K2.6 is ahead overall as of 2026-09-10, but check the category scores for your use.
- Is GPT-5.5 Instant better than Kimi K2.6 for coding?
- GPT-5.5 Instant scores higher in coding (61 vs 60 on the category index, where 50 is average).
- Is GPT-5.5 Instant better than Kimi K2.6 for agentic tasks?
- GPT-5.5 Instant scores higher in agentic tasks (71 vs 45 on the category index, where 50 is average).
- Which is cheaper, GPT-5.5 Instant 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 Instant or Kimi K2.6?
- GPT-5.5 Instant streams faster: 129 against 44 output tokens per second.
- Which has the larger context window?
- GPT-5.5 Instant accepts more context: 400k against 262k tokens.