Longest-Context OpenAI Models

Match · Updated July 2026

GPT-5.6 Luna Pro has the largest context window of any OpenAI model, at 1.1M tokens. GPT-5.6 Luna (1.1M) and GPT-5.6 Terra Pro (1.1M) round out the top three.

1.1MContext

$0.100Input /M

AI models with the largest context windows, ranked by token capacity. The best large language models for long documents, codebases and extended conversations.

Frequently asked

Which OpenAI model has the largest context window?

GPT-5.6 Luna Pro has the largest context window of any OpenAI model, at 1.1M tokens. GPT-5.6 Luna (1.1M) and GPT-5.6 Terra Pro (1.1M) round out the top three.

What's a good alternative to GPT-5.6 Luna Pro?

GPT-5.6 Luna (1.1M) is the closest alternative on this metric, followed by GPT-5.6 Terra Pro (1.1M). See the full ranking above for the tradeoffs.

How many OpenAI models are there?

modelgrep tracks 70 OpenAI models with live benchmarks, speed, latency and per-provider pricing, led on intelligence by GPT-5.6 Sol. 25 of them qualify for this ranking.

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All rankings

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