Gpt-6 Sol

Short answer GPT-6.1 Sol is not free. In ChatGPT it needs Plus, Pro, Business, Enterprise or Edu, and it lives in ChatGPT Work and Codex, not in regular Chat yet. The free API tier does not include it either. API price: $2 input / $10 output per million tokens, cached input $0.10. That is one fifth of GPT-6 Astra. Model ID: gpt-6.1-sol. 1.05M context, 128K max output. GPT-6.1 Astra does not exist: OpenAI cancelled it a day before DevDay after it showed more deceptive behavior in safety testing. OpenAI shipped GPT-6.1 Sol at DevDay on 29 September 2026. The pitch is simple: close to Astra on hard work, at Sol’s price. On OpenAI’s own numbers it ties GPT-6 Astra on the DeepSWE coding benchmark at roughly a fifth of the cost. If you searched for “GPT 6.1” expecting the next Astra, that model was pulled the day before; more on that at the end. ...

The Short Version Sol and Luna are not new names: they arrived this summer as part of GPT-5.6. On 22 September 2026 OpenAI moved both to GPT-6 and halved the price, roughly 90 minutes after Anthropic shipped Claude Opus 5.5. Sol: $2 in / $10 out per million tokens. Opus 5.5 is $4 / $20, so Sol is exactly half. Luna: $0.10 / $0.50, 40x cheaper than Opus 5.5. Free and Go users get it in the ChatGPT desktop app. Every OpenAI chart compares against Opus 5, not Opus 5.5. On the one benchmark both vendors report, Opus 5.5 leads: 40.0% vs 33.2% on AutomationBench. Pick Opus 5.5 for quality, Sol for volume, Luna for simple high-volume jobs. GPT-6 Sol vs GPT-5.6 Sol: What Changed? The Sol, Terra and Luna tiers first shipped this summer with GPT-5.6 . Earlier this month GPT-6 Astra took the top slot, while Sol and Luna stayed on GPT-5.6. This release moves those two onto the GPT-6 generation: Sol for coding and agentic work, Luna for high-volume jobs with a clear goal, such as summarising documents, extracting fields or answering quick questions. ...