Model by OpenAI

GPT-5.6 Sol

GPT-5.6 Sol is OpenAI's flagship in the 5.6 series, and it suits developers who want strong command-line and multi-step coding work through the API.

Checked 2026-11-05

GPT-5.6 Sol is OpenAI's flagship in the 5.6 series, and it suits developers who want strong command-line and multi-step coding work through the API. OpenAI's model page gives a context window of 1,050,000 tokens, 922,000 of them for input, and up to 128,000 tokens of output. It takes text and images and returns text only. The knowledge cutoff is 16 February 2026. Price is $4 per million input tokens and $20 per million output tokens, and OpenAI says that is promotional pricing lasting until 30 November 2026, so the rate may change soon. Prompts over 272,000 input tokens cost twice as much for input and one and a half times as much for output across the whole request. Reasoning effort runs from none to max, with medium as the default. It works on Chat Completions, Responses and Batch, but not Realtime or fine-tuning. OpenAI's page gives no release date, and OpenRouter listed it on 9 July 2026. OpenAI's deprecations page now recommends gpt-6-sol as a replacement for another model, so a newer line exists. We would use Sol for hard coding tasks and watch the promotion end date. Figures come from OpenAI's model pages and OpenRouter. We have not run it ourselves.

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Questions

What is the context window of GPT-5.6 Sol?

1,050,000 tokens, with up to 128,000 tokens of output.

How much does GPT-5.6 Sol cost?

$4 per million input tokens and $20 per million output tokens, checked 31 October 2026.

Can I run GPT-5.6 Sol on my own hardware?

No. The weights are not published, so you use it through the maker's API or a hosting provider.

Who makes GPT-5.6 Sol?

OpenAI makes it, and released it on 9 July 2026.

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