GPT-6.1 Sol
GPT-6.1 Sol is OpenAI's mid-tier GPT-6 model, matching Astra on agentic coding and computer use, with always-on reasoning and flagship-grade safeguards.
Model Overview
Capabilities, design details, and architectural traits
GPT-6.1 Sol - Near-Astra intelligence
GPT-6.1 Sol is OpenAI's mid-tier reasoning model, positioned between the flagship GPT-6 Astra and the small GPT-6 Luna. Its defining idea is near-Astra intelligence: it nearly matches Astra on agentic coding, computer use, and professional work. It is an upgrade to GPT-6 Sol, released one week after that model.
What sets it apart
| Trait | Detail |
|---|---|
| Agentic coding and computer use focus | Targets long-horizon software engineering in real codebases, multi-step business workflows, and demanding computer-use tasks. |
| Always-on reasoning | Supports low, medium, high, xhigh, and max reasoning effort; the none and minimal settings are not supported. |
| Flagship-grade safeguards | Rated Critical in cybersecurity and High in biology, so it ships with the same safeguards stack as GPT-6 Astra. |
Where it fits in the GPT-6 family
OpenAI frames the family as a capability curve: Astra for the best results, Sol for near-Astra capability, and Luna for fast, efficient everyday work at scale. GPT-6.1 Sol is the only 6.1 model, since OpenAI scrapped the planned GPT-6.1 Astra release. It is available in ChatGPT Work and Codex, and through the API as gpt-6.1-sol, with an Ultrafast variant offering up to 8x faster token generation in Codex.
Benchmark Performance
Independent evaluations · Artificial Analysis
Accuracy & Capability Details
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Evaluate specifications, pricing, and independent benchmark indices
| Model Details | |||
|---|---|---|---|
| General Info | |||
| Provider | OpenAI | Anthropic | Anthropic |
| Release Date | September 29, 2026 | September 22, 2026 | September 28, 2026 |
| Knowledge Cutoff | - | - | Jun 2026 |
| Context & Limits | |||
| Context Window | 1.1M Best Context Window | 1M | 1M |
| Pricing (per 1M tokens) | |||
| Input Pricing | $2 Best Input Pricing | $4 | $2 Best Input Pricing |
| Output Pricing | $10 Best Output Pricing | $20 | $10 Best Output Pricing |
| Modalities | |||
| Inputs | textimagefile | textimagefile | textimagefile |
| Outputs | text | text | text |
| Benchmarks (0-100) | |||
| Intelligence Index | 51.8 | 57.6 Best Intelligence Index | 56.0 |
| Coding Index | - | - | - |
| Agentic Index | - | - | - |
Humanity's Last Exam
Extremely difficult logical reasoning and knowledge.
Long Context Reasoning
Logical reasoning over long context windows.
SciCode Benchmark
Scientific coding and mathematical modeling.
Independent evaluation data provided by Artificial Analysis. To view the latest benchmarks and full details, visit their official site.
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