Automated page. Written and translated automatically by AI and checked against the sources by software; no human editor. SI-IQ is an index built from public benchmark results, not an IQ test. How it works
How smart is GPT-5.1?
GPT-5.1 is a model from OpenAI, released on Nov 13, 2025. Its SI-IQ is 120 (90% interval 115–125), estimated from 7 benchmark results by 2 independent evaluators. Its strongest area is Reasoning and its weakest is Knowledge.
Facts
- Developer
- OpenAI
- Released
- Nov 13, 2025
- Access
- API access
- Benchmarks used
- 7 results from 2 evaluators
- API price
- $1.25 input / $10 output per 1M tokens (developer's price list, Oct 18, 2026)
- Context window
- 272,000 tokens
Ability by area (SI-IQ, 90% interval)
Every benchmark result we used
Each score is one value exactly as the source published it: for Epoch AI the best of its run settings, for OpenRouter the median hosting provider (the developer's own hosting when it ran the test). “Implied SI-IQ” is the ability that this single result points to; the overall SI-IQ is their precision-weighted average.
| Benchmark | Score | Evaluated by | Source |
|---|---|---|---|
| Chess Puzzles | 42.0% | Epoch AI | Epoch AI Benchmarking Hub · data file |
| Mystery Game Puzzles | 19.0% | Epoch AI | Epoch AI Benchmarking Hub · data file |
| OTIS Mock AIME 2024–2025 | 88.6% | Epoch AI | Epoch AI Benchmarking Hub · data file |
| SWE-bench Verified (Epoch AI run) | 68.0% | Epoch AI | Epoch AI Benchmarking Hub · data file |
| GPQA Diamond | 87.6% | Epoch AI | Epoch AI Benchmarking Hub · data file |
| GPQA Diamond (OpenRouter run) | 86.9% | OpenRouter | OpenRouter benchmark datasets · data file |
| SimpleQA Verified | 48.0% | Epoch AI | Epoch AI Benchmarking Hub · data file |
| τ²-bench Airline (OpenRouter run) | 75.8% | OpenRouter | OpenRouter benchmark datasets · data file |
Human preference (Arena)
On the Arena leaderboard, where people vote between two anonymous answers, GPT-5.1 has a rating of 1,439 (1,435–1,442) from 44,434 votes (published Oct 15, 2026). Human preference is a different measure from benchmark ability and is not part of SI-IQ. Arena (Hugging Face)
Models with similar SI-IQ
| Model | SI-IQ | |
|---|---|---|
| GLM-5.3-FlashZ.ai (Zhipu AI) | 120 | GPT-5.1 vs GLM-5.3-Flash |
| GLM-5.2Z.ai (Zhipu AI) | 121 | GPT-5.1 vs GLM-5.2 |
| GPT-5OpenAI | 121 | GPT-5.1 vs GPT-5 |
| Kimi K2.6Moonshot | 121 | GPT-5.1 vs Kimi K2.6 |
| Kimi K2.5Moonshot | 119 | GPT-5.1 vs Kimi K2.5 |
Computed with SI-IQ method version 1.0.0. Read the full methodology
Data sources: Arena leaderboard dataset on Hugging Face (CC BY 4.0); Epoch AI, ‘Capabilities & benchmarking’ (CC BY 4.0); API list prices via LiteLLM's price table (MIT); each price links to the developer's pricing page; Source: OpenRouter (openrouter.ai), licensed under CC BY 4.0: reuse and republish with attribution to OpenRouter..