GPT-5.5 vs GPT-6 Sol

OpenAI's GPT-5.5 against OpenAI's GPT-6 Sol — price, context and what each is best at. Both are available through one OpenAI-compatible API.

AnyModel — you pay	GPT-5.5	GPT-6 Sol
Vendor	OpenAI	OpenAI
Input / 1M	$0.15	$0.2
Output / 1M	$0.15	$0.2
Context	400K	1M
Best for	Complex coding	Codex CLI

GPT-5.5

OpenAI's flagship for coding, agents and research-grade reasoning.

GPT-5.5 is OpenAI's top general-purpose model and the engine behind modern Codex: state-of-the-art coding, computer use and multi-step reasoning with a 400K-token window on this route. The default pick when you want one model that handles everything.

More about GPT-5.5 →

GPT-6 Sol

OpenAI's GPT-6 workhorse for coding and everyday work.

GPT-6 Sol is the everyday tier of the GPT-6 line, trained with the same methods as Astra: OpenAI's workhorse for agentic coding and day-to-day engineering, with long autonomous sessions, repo-scale edits, reliable tool calling and reasoning effort up to max, at a fifth of Astra's vendor price. The default pick for most Codex work; reach for Astra when the task is unusually hard.

More about GPT-6 Sol →

Quick take: pick GPT-5.5 when cost matters most; pick GPT-6 Sol when you need the largest context. With AnyModel you don't have to choose up front — switch the model id any time.

FAQ

Which is cheaper, GPT-5.5 or GPT-6 Sol?

GPT-5.5 is cheaper on output tokens ($0.15 vs $0.2 per 1M).

Which has a larger context window, GPT-5.5 or GPT-6 Sol?

GPT-6 Sol has the larger context window (1M).