GPT-6.1 Sol (Reasoning)

by OpenAI

GPT-6.1 Sol (Reasoning) is a reasoning model from OpenAI, released on September 29, 2026. It has a 1.1M-token context window and can generate up to 128K output tokens. API pricing is $2 per 1M input tokens and $10 per 1M output tokens. It ranks #6 of 220 models by Intelligence Score with a score of 53.9.

GPT-6.1 Sol is OpenAI's GPT-6.1 model delivering near-Astra performance for complex coding, computer use, and professional work at a lower cost. The API model id is gpt-6.1-sol. It accepts text and image input with text output, supports low, medium (API default), high, xhigh, and max reasoning effort (but not none or minimal), and provides a 1,050,000-token context window with up to 128,000 output tokens. Use the Responses API for tool calling; Chat Completions is supported without tool calling. Responses API tools include web and file search, image generation, code interpreter, hosted shell, apply patch, skills, computer use, MCP, and tool search; it also supports streaming, function calling, and structured outputs. Standard per-million-token pricing is $2 input, $0.10 cached input, $2.50 cache writes, and $10 output. Prompts above 272K input tokens cost 2x input/cache and 1.5x output across the full request. Batch and Flex cost 50% of Standard; Fast costs 2x. Regional processing adds 10% where available. Launch benchmarks are OpenAI-reported; effort and evaluation variants are recorded with each score.

Key specs

Compare on the AI leaderboard · All AI models

More models from OpenAI

• GPT-6 Astra (Reasoning) — OpenAI
• GPT-5.6 Terra (Reasoning) — OpenAI
• GPT-6 Sol (Reasoning) — OpenAI
• GPT-5.5 Pro (Reasoning) — OpenAI
• GPT-6 Luna (Reasoning) — OpenAI
• GPT-5.2 Pro — OpenAI