Gemini 4 Carbon is #1, and you can't use it yet

Why it matters

Google's new top model is ranked first and already has a price, and nobody outside a small circle can call it yet, so here is what is known and what to plan with until it opens.

I'm curious about this one. Google lagged for a long time, but Argon was a big step, and with its current discounted price we use it more and more. Let's see if Carbon is still on top when it's public.

What Google announced

What Google announced

Google published Gemini 4 Carbon: our next frontier model on 28 October 2026, written by Koray Kavukcuoglu, SVP of Google DeepMind and Chief AI Architect. Google calls Carbon its strongest model, with state-of-the-art cybersecurity and long horizon capabilities, and says it builds on Gemini 4 Argon, which was launched two weeks ago.

Built for long jobs. Google says its teams have seen Carbon run for days, pushing through dead ends on multi-step engineering work like finding the root cause of subtle bugs across large codebases and patching them. That is Google's account of its own internal use, with no number attached.

For automations, one passage matters most. When something doesn't add up, Google says Carbon retrieves the relevant sources and shows you the discrepancies before acting, instead of guessing or forcing a path forward. In Google's own testing, it cuts unsupported claims by about 2x over Argon. A model that asks before it guesses. We'd like to meet it.

Most of the post is about security. In Google's own table Carbon scores highest of the models with a score on all three security tests: SEC-bench Pro 88.2 percent (finding vulnerabilities), ExploitGym 54.8 percent (exploiting them) and CWE-bench 71.0 percent (patching them). Google ran SEC-bench Pro and ExploitGym itself. Its method note says the other labs' numbers are their own reported ones unless it says otherwise, and CWE-bench comes from Collinear AI's public leaderboard.

Sources: Google: Gemini 4 Carbon, our next frontier model (28 October 2026) and Google DeepMind: evaluation method for Gemini 4 Carbon (PDF, read 31 October 2026)

Number one

Number one, by one point

Artificial Analysis ranks Gemini 4 Carbon (High) first of 58 models on its Intelligence Index v5.0, at 59. Next: Claude Opus 5.5 (max with fallback) at 58, GPT-6 Astra (max) at 57, GPT-6.1 Sol (max) at 55. Google's post quotes the same rank. First place, by one point.

The same page draws Carbon's bar checkered, with the legend No publicly available API. Artificial Analysis lists Carbon at USD 4 per million input tokens and USD 20 per million output tokens, which is the price Google gives for after its introductory period. It puts the cost of one index task at USD 7.76 and calls the model very verbose: 200 million output tokens on the index, against a median of 70 million. Thorough, and it shows on the bill.

Google's own table also shows where Carbon is not first. GPT-6 Astra leads FrontierSWE 2 (65.5 percent against Carbon's 61.2) and Claude Opus 5.5 leads OSWorld-2.1 (87.2 against 81.5). On AutomationBench, Zapier's test of business automation, Carbon scores 53.9 percent and Argon 51.3.

Sources: Artificial Analysis: Gemini 4 Carbon (read 31 October 2026) and Google: Gemini 4 Carbon, our next frontier model (28 October 2026)

What it will cost

What it will cost

Google says Carbon will launch at the same introductory price as Argon: USD 2 per million input tokens and USD 10 per million output tokens, with cached input 95 percent off the input price. A footnote adds that after the introductory period, USD 4 and USD 20 apply. The post gives no end date for Carbon's introductory period.

Argon's has one. Google's Gemini API price list says USD 2 and USD 10 through 30 November 2026, then USD 4 and USD 20 from 1 December 2026, and context caching USD 0.10, then USD 0.20. Argon is not on the free tier. We read the list again on the evening of 31 October: same prices, same dates, still no Carbon row.

Sources: Google: Gemini 4 Carbon, our next frontier model, with footnote 1 (28 October 2026) and Google: Gemini Developer API pricing (read 31 October 2026)

Who can use it

Who can use it, and when

Google says that starting the week of 28 October, Carbon goes to a subset of cyber defenders, and then, step by step, to more trusted partners through its Fairwind Program. Google says it is still gathering feedback and working on guardrails before it makes Carbon available to developers, businesses and consumers, as soon as possible. No date.

Fairwind gives high-priority defenders, like governments, healthcare providers and telecommunications services, early access. Google runs background checks on organizations that apply and says it works with over 650 partners. On 31 October the Fairwind page still describes access to Argon and does not name Carbon, so how many of those partners get Carbon is not said.

We checked on 31 October 2026, in the afternoon and again in the evening. Google's Gemini API model list shows one Gemini 4 model: Argon. The API price list, the API changelog, the Gemini app release notes and the Google Cloud model list don't mention Carbon. Artificial Analysis marks it No publicly available API. Arena posted first impressions of a Carbon preview on 28 October, so a few testers had one. Whether anyone else can reach it there, Arena doesn't say.

So for now you can't check any of this on your own work. If you want Google's top model you can call today, that's Argon, at USD 2 and USD 10 until 30 November, and double from 1 December, so budget for that now. When Carbon opens, try it on one real job before you move anything to it.

Sources: Google: Gemini 4 Carbon, our next frontier model (28 October 2026), Google DeepMind: Fairwind Program (read 31 October 2026), Google: Gemini API models (read 31 October 2026), Google: Gemini API changelog (read 31 October 2026), Google: Gemini app release notes (read 31 October 2026), Google Cloud: Google models (read 31 October 2026), Artificial Analysis: Gemini 4 Carbon (read 31 October 2026), and Arena on X: first impressions of the Carbon preview (28 October 2026)

Argon went the same way

Read the sources

Read the sources

Every number above comes from these pages. Where a page can change, the date we read it is next to it.

• Read the postGoogle: the Carbon launch post

  What Carbon is for, the rollout order, the introductory price and footnote 1 with the later price.

  

• Open the pageArtificial Analysis: Gemini 4 Carbon

  The rank, the cost per index task, the token count and the No publicly available API legend.

  

• Open Google's price listGoogle: Gemini API pricing

  Argon's price through 30 November and from 1 December. No Carbon row yet.

  

• Open the model listGoogle: Gemini API models

  The model list developers can call. Under Gemini 4, one model: Argon.

  

• Open the PDFGoogle DeepMind: how the tests were run

  The method behind Google's table: settings, and which numbers Google ran and which the labs reported.

• Open the pageGoogle DeepMind: Fairwind Program

  Who gets early access, the background checks and the 650 partners. It still names Argon.

• Read the postGoogle: Argon now available

  13 October: where Argon opened and for whom, 13 days after its announcement.

• Open the postArena on X: the Carbon preview

  First impressions of a Carbon preview on launch day: 3D generations, creative prompts and UI tasks.

Read on 31 October 2026, in the afternoon and again at about 19:30 CET. Carbon had no public API at either read. Check again before you rely on this: most of this page changes the day Carbon opens.