GPT-6 Astra

by OpenAI - closed weights. Top tier of the GPT-6 lineup: “our most capable model for the most demanding work” (OpenAI model page). Hub: gpt-5-and-gpt-6-family.

Item	Value (OpenAI API docs)
API model ID	gpt-6-astra (single snapshot)
Released	2026-09-03 (API changelog); press coverage 09-03/09-04
Context / output	1,050,000 window, 922k max input, 128k max output
Knowledge cutoff	2026-04-30
Pricing	token-based; Batch/Flex -50%, fast mode 2x; surcharge above 272K input tokens
Reasoning effort	low up to max

Positioning

Astra is the premium tier for hard end-to-end work (reasoning, coding, computer use, research, document creation). gpt-6-dot-sol and gpt-6-dot-luna are cheaper tiers built with similar methods; gpt-6-dot-1-sol (2026-09-29) is described as “near-Astra” at one fifth of the price.

Availability

• API: live from launch.
• ChatGPT: OpenAI’s launch post on X says Pro, Enterprise and Business Premium users get it in ChatGPT Work and Codex, with Plus and Business “in a few days”. A developer-forum thread reports that Plus access was initially limited to Work/Codex, not plain chat. Plan details move fast: check OpenAI’s help center (page was not fetchable on 2026-09-30).
• Also reported on AWS (secondary source, unverified).

Caveats

• A “GPT-6.1 Astra” was reportedly cancelled over internal safety tests (WSJ/CNBC reports seen only as search snippets; CNBC page blocked) - treat as unverified.
• Some press sources use inconsistent tier naming (Terra appears in GPT-5.6 only; no GPT-6 Terra on the models page).

Sources

• https://developers.openai.com/api/docs/models/gpt-6-astra (2026-09-30)
• https://developers.openai.com/api/docs/changelog (2026-09-30)
• https://9to5mac.com/2026/09/04/openai-releasing-major-upgrade-to-chatgpt-and-codex-with-gpt-6-astra-details-here/ (search snippet, 2026-09-30)
• https://community.openai.com/t/clarification-needed-gpt-6-astra-was-announced-for-all-chatgpt-plus-users-but-plus-access-is-currently-limited-to-work-codex/1395038 (snippet, 2026-09-30)