On October 28, 2026, Google unveiled Gemini 4 Carbon, which it calls its most capable model so far. It arrives two weeks after Gemini 4 Argon and is aimed mainly at coding and cybersecurity. For now only a group of cyber defenders can use it; there is no public release date.
What we know
- Who has it: per Google's blog, starting the week of the announcement Carbon is available to "a subset of cyber defenders." Access will gradually extend to more trusted partners through its Fairwind Program.
- Who doesn't: Google says it will keep gathering feedback and refining guardrails before opening it to developers, businesses and consumers. It promises to do so "as soon as possible," with no date.
- Outside testing: Google says it takes part in the U.S. government's voluntary pre-release model testing process.
- Announced pricing: Google says Carbon will launch at the same introductory price as Argon: $2 per million input tokens and $10 per million output tokens, with cached input 95% cheaper. After the introductory period it moves to $4 and $20. The post does not say how long that period lasts.
- Google's own benchmarks: first place on version 5.0 of the Artificial Analysis Intelligence Index, with a score of 59; fourth place on WebDev Arena (1768 Elo), up 89 points.
- Security results: Google reports 88.2% on SEC-bench Pro (finding vulnerabilities) and 54.8% on ExploitGym. It also says Carbon resisted every evaluated attack on Gray Swan's indirect prompt injection benchmark (0.0% success rate).
- Long tasks: according to Google, it can work for days on multi-step engineering tasks such as finding the root cause of a bug and patching it across a large codebase.
- What the post leaves out: it does not mention Search, AI Mode or the Gemini app, and gives no API model name.
What changes and what doesn't
- Nothing changes yet for almost everyone: neither the Gemini app nor the public API offers Carbon. Gemini users stay on Argon or other models.
- There is now a price reference: if you use it via the API one day, Carbon would cost the same as Argon at launch. As this article's own math: a request with 10,000 input tokens and 2,000 output tokens would cost about $0.04 at the introductory price and about $0.08 at the final price.
- The numbers are Google's: the benchmark results come from the company itself. They say nothing about how it will perform on a specific business's tasks.
- Security is the focus: Google is giving it to defenders first, and its own figures show it can exploit flaws (ExploitGym), not just find them.
How to tell if it affects you
- If you are searching for "Gemini 4 Carbon" to try it: you can't yet, unless you are one of Google's cyber defense partners. Be wary of sites or apps claiming to offer it today.
- If your business uses Gemini via the API: there is nothing to migrate. When it ships, test it on your own tasks before switching and compare cost and quality against Argon.
- If you run a website: the underlying message is that AI now finds software flaws quickly. Keep your CMS (WordPress, Drupal), its plugins or modules, and your hosting's PHP version up to date.
- If you use AI agents connected to your site or inbox: indirect prompt injection is a real risk. Until you have a more resistant model, keep those agents' permissions tight.
- For budgeting: plan with $4 and $20 per million tokens, the announced final price, not the introductory one.
Related: Gemini 4 Argon Is Now Available: Who Can Use It
Sources
Updates: when Google opens Carbon to developers, businesses or the Gemini app, it will be added here with a link.