Term
GPT-6.1 Sol
GPT-6.1 Sol (September 29, 2026) is OpenAIs low-cost coding and agentic model — the successor to GPT-6 Sol after just seven days, with near GPT-6 Astra intelligence at roughly a fifth of the price. Available via boostN.
GPT-6.1 Sol — explained in more detail
GPT-6.1 Sol is OpenAIs low-cost model for coding and agentic work, unveiled on September 29, 2026 at the OpenAI DevDay. It replaced GPT-6 Sol, which had shipped only seven days earlier — Artificial Analysis summed up the move as “replaces GPT-6 Sol after just 7 days.” The pitch: near the intelligence of the flagship GPT-6 Astra, but at a fraction of the cost. On the Artificial Analysis Intelligence Index, Sol 6.1 scores 52 points, just behind Astra (53) and further behind Claude Sonnet 5.5 (56) and Claude Opus 5.5 (58) — four points above its direct predecessor GPT-6 Sol.
Key facts
- Release: September 29, 2026 (OpenAI DevDay), an upgrade of GPT-6 Sol after just seven days.
- Pricing (per 1M tokens): $2 input, $10 output, $0.10 cached input (95 percent below the input price), $2.50 cache write. For prompts above 272,000 tokens the whole request is billed at 2x input/cache and 1.5x output.
- Context: 1,050,000 tokens input, up to 128,000 tokens output.
- Reasoning effort: low, medium (default), high, xhigh, max — no none/minimal.
- Access: ChatGPT Work and Codex (Plus, Pro, Business, Enterprise, Edu), API (model ID
gpt-6.1-sol), OpenRouter (openai/gpt-6.1-sol), Vercel AI Gateway and GitHub Copilot. Not in Free/Go or the standard chat. - Ultrafast: announced for Codex — up to 8x faster token generation at six times the standard price.
Example / Practical use
On the coding benchmark DeepSWE v1.1, Sol 6.1 reaches 75.2 percent per OpenAI, matching GPT-6 Astra (74.1 percent) — at roughly a fifth of the cost per task. On OSWorld 2.0 (computer-use) it hits 71.4 percent, just over two points behind Astra (73.5 percent), but at a fraction of the cost. That positions Sol 6.1 as a cheap workhorse for coding and agentic workloads: close to top quality without the price tag. The model is available directly via boostN.
Distinction
GPT-6.1 Sol is not the most intelligent model on the market — on the Artificial Analysis Intelligence Index the entire Claude lineup (Sonnet 5.5, Opus 5.5) sits ahead of it, and GPT-6 Astra stays a point in front too. Its edge is value: near-Astra quality at about a fifth of the token cost. Where maximum model quality matters, Astra or the Claude models stay ahead; where cost per task decides, Sol 6.1 is the cheaper pick. Against Claude Sonnet 5.5 (same $2/$10 list price), Sol 6.1 is markedly slower at around 67 tokens per second.