GPT-6 Astra

GPT-6 Astra shipped on 3 September 2026 at $10 per million input tokens and $50 output — 2.5× the rate of GPT-5.6 Sol — with cached input at $1, batch at half price and a Fast mode at double. It carries a 1,050,000-token context window, 128K maximum output and an April 2026 knowledge cutoff. OpenAI reports 72.6% on OSWorld 2.0 computer use, 97.6% on FrontierMath Tier 4 and 100% on ExploitBench. Its ARC-AGI-3 result is two numbers, not one: 99.9% under OpenAI's Provider Adapter harness and 62.7% under the shared Standard harness, per ARC Prize's own report, which adds that saturating the benchmark "would not represent proof of achieving AGI". Astra is the first model OpenAI has designated as reaching the "critical" cybersecurity threshold in its preparedness framework; the public version refuses proof-of-concept exploit requests, and rollout began with vetted enterprise customers in the gated Daybreak programme ahead of ChatGPT plans and the API.