GPT-6 Sol
OpenAI's mid-tier GPT-6 model for coding and agentic work
Paid
Reasoning
1050000
context tokens
Undisclosed
parameters
Proprietary
license
Sep 2026
released
OpenAI released GPT-6 Sol on September 22, 2026, alongside the cheaper GPT-6 Luna, positioning both below the earlier GPT-6 Astra flagship in the GPT-6 lineup. Sol reads up to 1.05 million tokens of context and writes up to 128,000 tokens of output, aimed at coding and agentic tasks rather than Astra’s recurrent-depth reasoning. API pricing runs $2 per million input tokens and $10 per million output tokens, with a $0.20 rate for cached input.
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