Google has made Gemini 4 Carbon available to paying developers, enterprises and Google AI Ultra subscribers, two weeks after first releasing the model to a small group of cybersecurity defenders. The wider rollout began on 10 November 2026.

Carbon is Google DeepMind’s strongest model, built for long-horizon agentic work, complex software engineering and scientific reasoning. It was first announced on 28 October, when access was limited to a subset of cyber defenders through Google’s Fairwind programme. That restricted phase is now over for the general configuration of the model, although the specialised cybersecurity configuration remains gated through Fairwind applications.

Who can use Gemini 4 Carbon now

Paying developers can use Carbon through the Gemini API in Google AI Studio and Android Studio, while enterprises can access it through Gemini for business. Google AI Ultra subscribers can use it in the Gemini app, AI Mode in Search and Google Antigravity.

Google has not said when, or whether, lower-tier subscribers or free users will get access. In the Gemini app, Gemini 4 Argon remains available for AI Pro subscribers and above, while Gemini 3.1 Pro has been removed from the model picker with this launch. In the picker, Argon is described as the choice for “code and analysis”, while Carbon is listed for “most complex work”.

What Gemini 4 Carbon costs

Carbon launches at the same introductory price as Gemini 4 Argon: $2 per million input tokens and $10 per million output tokens. That introductory pricing runs until 30 November 2026. From 1 December, the price rises to $4 per million input tokens and $20 per million output tokens.

Carbon is excluded from the Gemini API free tier, and every token processed is billed, including tokens used for reasoning. Google is also expanding a research programme that offers selected scientists both Argon and Carbon in Antigravity’s highest usage tier free for six months, with applications still open.

What the model can do

According to Google’s model card, Carbon builds on Argon’s pre-training foundation and architecture, with additional post-training for deep reasoning, extended verification and multi-step agent workflows. It has a 1 million token context window and a March 2026 knowledge cutoff.

The model card’s results, current as of October 2026, put Carbon at 59 on the Artificial Analysis Intelligence Index, compared with 50 for Argon, and at 96.2% against 84.2% on a long-context test running from 256,000 tokens to 1 million tokens. Google also says Carbon did not cross its threshold for a material capability change relative to Argon, so a full new critical-capability assessment was not required.

Google Antigravity is also previewing /swarm, a tool that turns one prompt into a team of AI agents working together.

Frequently asked questions

Is Gemini 4 Carbon free? No. It is available to paying developers and enterprises through the Gemini API, and to Google AI Ultra subscribers. It is not included in the Gemini API free tier.

How much does Gemini 4 Carbon cost? The introductory price is $2 per million input tokens and $10 per million output tokens until 30 November 2026. From 1 December, the price becomes $4 and $20 per million tokens.

Where can Ultra subscribers use Carbon? In the Gemini app, AI Mode in Search and Google Antigravity.

Sources: 9to5Google and Unite.AI.