Gemini 4 Carbon is Google's strongest model, but only cyber defenders get it

Google launched Gemini 4 Carbon on Oct. 28, calling it its strongest model. It is not open to the public. Google is giving it first to a subset of cyber defenders, and has not said when developers, businesses or consumers get it.

What changed

Google describes Carbon as "our strongest model with state-of-the-art cybersecurity and long horizon capabilities." This is the model we first covered as a staff-testing report.

Google says it ran these benchmarks without guardrails, and that Carbon scores 88.2% on SEC-bench Pro (finding vulnerabilities), 54.8% on ExploitGym (exploiting them) and 71.0% on CWE-bench (patching them).

Those are Google's numbers. We have not run the model. Google says it is still gathering feedback and iterating on guardrails before making Carbon available to developers, businesses and consumers.

Access starts the week of the announcement, and more trusted partners are added gradually through the Fairwind Program. Google did not state what that program requires.

Who is affected

Today, only the cyber defenders Google selected. Developers, businesses and consumers cannot use Carbon. Google says it will make the model available as soon as possible and gave no date, so we are not guessing at one.

Argon, the earlier Gemini 4 model, is already in the Gemini app. Google says Carbon's score on the Gray Swan indirect prompt injection test is a 0.0% attack success rate, against 0.7% for Argon.

Google says it is taking part in the U.S. government's voluntary pre-release model testing process.

What this means for you

If you are not a security team in Google's group, nothing changes today, and Google gave no date for a wider release.

Price and ranking are secondary but concrete. Google lists an introductory $2 per million input tokens and $10 per million output tokens, with cached input 95% off. After the introductory period, it is $4 and $20. Google did not say when that period ends.

Google also says Carbon ranks first on the Artificial Analysis Intelligence Index v5.0 with a score of 59, and fourth on WebDev Arena at 1769 Elo, up 89.

What we checked

All figures come from Google's launch post, checked at 1:44 p.m. ET on Oct. 28. We have not tested Carbon and could not verify any benchmark independently. Google did not state a public release date, the end of the introductory price or what the Fairwind Program requires.