Gemini 4 Carbon opened on November 10, 2026, and the main paths into it are paid. Eligible scientists can apply for six months of free access through Google's research program, reviewed on a rolling basis.
In the Gemini app, Carbon is rolling out to Google AI Ultra subscribers. Google's plans page shows the AI Plus and AI Pro plans include Gemini 4 Argon, not Carbon. Ultra starts at $99.99 per month in the US on monthly billing (checked November 10, 2026).
Developers can build with Carbon on the paid Gemini API tier in Google AI Studio and Android Studio: $2 per million input tokens and $10 per million output tokens through November 30, 2026. Both prices double on December 1, 2026, and the free API tier doesn't include Carbon.