GPT-6 Astra
GPT-6 Astra is OpenAI's flagship frontier model, released September 3, 2026 and described by OpenAI as its most capable and most aligned model, built for the hardest end-to-end work in coding, computer use, browsing, research and professional tasks. On the API it offers a 1,050,000-token context window with up to 128,000 output tokens, a knowledge cutoff of April 30, 2026, text and image input with text output, and support for function/tool calling, built-in tools (web search, file search, computer use), Structured Outputs and streaming; reasoning effort supports low, medium, high, xhigh and max (none is not supported, and custom temperature/top_p and logprob are unavailable). Standard API pricing is $10 per 1M input tokens and $50 per 1M output tokens, with cached input at $1.00, cache writes at $12.50, and a long-context tier above 272K input tokens at $20/$75 ($2.00 cached, $25.00 cache writes); Batch and Flex are priced at 50% of Standard rates and Fast mode at 2x. Access is being rolled out gradually, with parts of it gated behind OpenAI's Trusted Access / Daybreak program as the first model to reach the Critical cybersecurity capability level under its Preparedness Framework.