Google expanded Gemini 4 Carbon access on Nov. 10, the same day Simon Willison’s llm-gemini plug-in added a command-line route for developers, as introductory API rates approach a scheduled increase after Nov. 30.
Developers can use the model through paid API access in Google AI Studio or Android Studio, the company said. Businesses can access Carbon through Gemini for business. Google is also gradually bringing the model to its Gemini app and Search’s AI Mode for Google AI Ultra subscribers.
Google lists introductory rates of $2 per 1 million input tokens and $10 per 1 million output tokens. After the introductory period expires on Nov. 30, 2026, the listed rates rise to $4 and $20, respectively. The change applies to per-token prices; a customer’s total bill depends on how many tokens the account uses.
A Nov. 10 release of Simon Willison’s llm-gemini plug-in added support for Carbon. Users can select it with llm -m gemini-4-carbon, a model identifier that also appears in Google’s AI Studio documentation. The project README directs users to install the plug-in alongside the LLM command-line tool and configure a Gemini API key.
Google says Carbon is designed for complex, long-running work and uses more tokens than Gemini 4 Argon. With charges based on token volume, usage patterns affect the cost of running the model in addition to the listed per-token rates.
Google’s first announcement of Carbon, on Oct. 28, limited its initial rollout to some cyber defenders in the Fairwind Program. The introductory API pricing period ends Nov. 30; Google has not specified a cutoff time or time zone for the change.
