GPT-6 Sol

GPT-6 Sol is the mid-tier model of OpenAI’s GPT-6 family, announced on 22 September 2026 alongside GPT-6 Luna and served through the API as gpt-6-sol. Its documentation page gives a 1,050,000-token context window, up to 128,000 output tokens, text and image input with text output, and a knowledge cutoff of 20 April 2026. The price is $2 per million input tokens, $10 per million output tokens and $0.20 per million cached input tokens — half the $4 and $20 that GPT-5.6 Sol was sold at, which OpenAI attributes to caching and inference improvements rather than to a smaller model. The same announcement raised the default cache hit rate and put the discount on cached input reads at 90 per cent. Availability at launch was ChatGPT Work and Codex for Plus, Pro, Business, Enterprise and Edu users, and the API; it was not in Chat on the day. Artificial Analysis, measuring independently, scores it 48 on version 4.3.2 of its Intelligence Index and records 126.0 output tokens per second and 77 million output tokens to complete the index, with a blended rate of $1.54 per million tokens on a 7:2:1 cache-hit, input, output mix. OpenAI’s own figures — 33.2 per cent on AutomationBench 1.0.6 at xhigh effort, 56.4 per cent on Agents’ Last Exam V1 at max effort, 68.8 per cent on DeepSWE v1.1 and 60.5 per cent on OSWorld 2.0 offline at xhigh — are its own evaluation and are not stored as scores. The buyer’s point in that table is not the score but the cost per task printed beside it: OpenAI puts GPT-6 Sol at $0.27 a task on AutomationBench against 11.1 times that for a rival at max effort, which is the sort of comparison to reproduce on your own workload before believing it. OpenAI also publishes a deprecations page with dated shutdowns; on the day this listing was written it carried the removal of the Videos API on 24 September 2026 and of twelve legacy snapshots on 23 October 2026.