GPT-6.1 Terra

GPT-6.1 Terra is a newer OpenAI model released 2026-10-26, priced between Luna and Sol. OpenRouter lists $1 per million input tokens and $5 output, with a 1,050,000-token context and text, image and PDF input. It is the same price as the older GPT-6 Terra on OpenAI's page, so the update changes the model but not the budget. It is closed and proprietary. We would suggest it for teams that find Luna too weak and Sol too costly, for example in support drafting or code review at volume. The limit is that a Pro variant is also listed at the same price, and we have not found a clear public explanation of the difference, so we flag that as unconfirmed and tell readers to check OpenAI's docs before choosing. Prices and specifications come from the OpenRouter listing we checked on 31 October 2026, and we have not tested the model ourselves.