Google DeepMind announced Gemini 4 Carbon on Wednesday, October 28, calling it its strongest model yet, with state-of-the-art cybersecurity and long-horizon capabilities. It arrives just two weeks after Gemini 4 Argon, and Google says it ranks first on Artificial Analysis's Intelligence Index v5.0 with a score of 59, a point ahead of Claude Opus 5.5.

Cybersecurity is the headline: Google reports 88.2% on SEC-bench Pro for finding vulnerabilities, 54.8% on ExploitGym and 71.0% on CWE-bench for patching, run without guardrails. It also says Carbon more than doubles Argon's success rate at generating secure code. Those security figures are Google's own, not independently reproduced.

Access starts narrow. A subset of cyber defenders gets Carbon this week through Google's Fairwind Program, then more trusted partners, while Google takes part in the US government's voluntary pre-release testing process. Wider access for developers, businesses and consumers is promised as soon as possible, with no date; introductory pricing is $2 per million input tokens and $10 per million output, rising to $4 and $20 later.