What to know first
If you already pay for AI Ultra, you can try Carbon from the model picker, but expect it to use your limits faster; Google has not published a separate Carbon cap. AI Pro users do not need to upgrade just for Carbon: Google says Argon still suits most work, and Ultra starts at $99.99 a month, several times the price of AI Pro. If you only want Carbon for development, the paid Gemini API at the introductory rate before November 30 may cost less than upgrading, but API usage is billed separately and is not included in any Google AI plan.
What did Google release on November 10?
Google's blog post "Gemini 4 Carbon is now available", dated November 10, 2026, opened Carbon to developers, enterprises, scientists and consumers. Two weeks earlier, Carbon had only been available to a group of cybersecurity defenders through the Fairwind Program. Google calls Carbon its strongest model, built for long-horizon agentic work, complex multi-step coding and debugging, and open-ended scientific research.
The line that matters for subscribers: Carbon is rolling out to all Google AI Ultra subscribers in Google Antigravity, the Gemini app and AI Mode in Search. The official Google Gemini X account confirmed it in a post on November 10 at 16:06 UTC (November 11, 00:06 Singapore time), saying Carbon is rolling out to AI Ultra subscribers on desktop, mobile and web.
| Item | What Google says |
|---|---|
| Release date | November 10, 2026 (Fairwind Program only for the two weeks before) |
| Subscribers | Google AI Ultra: Gemini app, AI Mode in Search, Google Antigravity |
| Developers | Paid tier of the Gemini API (Google AI Studio, Android Studio) |
| Enterprises | Gemini for business (API or model drop-down), Antigravity, CodeMender |
| Role versus Argon | Argon suits most software engineering and knowledge work; Carbon is for the hardest tasks and uses more tokens than Argon |
| Plan prices | No price change announced |
Sources: Google: Gemini 4 Carbon is now available (November 10, 2026)Google Gemini on X: Gemini 4 Carbon rolling out to Google AI Ultra (November 10, 2026, 16:06 UTC)
Which Google AI plans can use Gemini 4 Carbon?
On the US Gemini subscriptions page checked on November 11, 2026, AI Ultra's Gemini app benefits read "Highest access to Gemini 4 Argon" and "Highest access to Gemini 4 Carbon", and its Search benefits also name Carbon. AI Pro lists Gemini 4 Argon, the Pro model and the Flash model; AI Plus lists the Flash model. Carbon does not appear in AI Pro or AI Plus benefits.
Ultra has two tiers: $99.99 a month gives 5x AI Pro usage and $199.99 a month gives 20x. The Gemini Help Center says AI Plus gets 2x the standard limits and AI Pro 4x. Limits are compute-based, taking into account prompt complexity, the models and features used, and chat length, and they refresh every five hours until you reach the weekly limit. For full prices, context windows and regional prices, see Google AI Plus vs Pro vs Ultra.
| Plan | Gemini 4 Carbon | Gemini 4 Argon | Usage multiple (Gemini Help Center) |
|---|---|---|---|
| Free | No | No | Standard limits |
| AI Plus | No | No | 2x standard |
| AI Pro | No | Yes | 4x standard |
| AI Ultra ($99.99/mo) | Yes | Yes (highest access) | 5x AI Pro |
| AI Ultra ($199.99/mo) | Yes | Yes (highest access) | 20x AI Pro |
Sources: Google: Gemini subscriptions (Google AI Plus, Pro and Ultra)Google: Gemini 4 Carbon is now available (November 10, 2026)Gemini Apps Help: Gemini Apps limits and upgrades for Google AI subscribers
Carbon or Argon, and will Carbon burn through limits faster?
Google is direct about it: Argon remains the ideal choice for most software engineering and knowledge work, while Carbon is built for tasks that test the limits of a model, such as complex multi-step coding and debugging and open-ended scientific research, using more tokens than Argon to explore thoroughly, reason deeply and run extended verification loops.
Gemini app limits are compute-based, and the model you use is one of the factors. Google has not published a separate Carbon count or share on Ultra, so this article does not estimate how many Carbon prompts an Ultra tier covers. What is clear is that the same task will usually use more of your limit on Carbon than on Argon. When you hit the limit, the Help Center says subscribers can continue with Flash-Lite or wait for the refresh.
| Item | Gemini 4 Argon | Gemini 4 Carbon |
|---|---|---|
| Google's recommended use | Most software engineering and knowledge work | Hardest long tasks, complex multi-step coding and debugging, open-ended research |
| Token use | Lower | Higher than Argon |
| Subscription access | AI Pro and above | AI Ultra only |
| API introductory price (per million tokens) | $2 input, $10 output | $2 input, $10 output (same as Argon) |
Sources: Google: Gemini 4 Carbon is now available (November 10, 2026)Gemini Apps Help: Gemini Apps limits and upgrades for Google AI subscribers
How do you use Carbon in Antigravity and AI Studio?
The Antigravity blog says that from November 10, Google AI Ultra subscribers can build with Carbon in the Antigravity desktop app, the Antigravity CLI and the IDE extensions. The /swarm preview, which hands one prompt to a coordinated team of agents, is rolling out in the Antigravity app and CLI at the same time. Google's developer blog adds that Ultra subscribers can try Carbon in Google AI Studio.
On the subscriptions page, AI Pro gets "entry" rate limits to the agent model in Antigravity, Ultra 5x gets "higher" and Ultra 20x gets "highest". The Antigravity announcement only names Ultra for Carbon. If you are comparing what Codex, Claude Code and Antigravity offer at each price point, see Codex vs Claude Code vs Antigravity.
| Surface | Who can use Carbon |
|---|---|
| Antigravity app, CLI, IDE extensions | Google AI Ultra subscribers |
| /swarm (preview) | Rolling out in the Antigravity app and CLI |
| Google AI Studio | Ultra subscribers can try it; paid-tier API developers |
| Gemini API | Paid-tier developers, billed per token |
| Scientists and researchers | Can apply for six months of free access to Antigravity's highest usage tier with Argon and Carbon, subject to eligibility, capacity and selection |
Sources: Google Antigravity Blog: Gemini 4 Carbon and /swarm (November 10, 2026)Google: Gemini 4 Carbon is now available for developersGoogle: Gemini subscriptions (Google AI Plus, Pro and Ultra)
How much does the Gemini 4 Carbon API cost, and what changes after November 30?
Google says Carbon is available through the Gemini API in Google AI Studio and Gemini for business to all paying developers and enterprises, at the same introductory price as Gemini 4 Argon: $2 per million input tokens and $10 per million output tokens. The introductory period ends on November 30, 2026, after which the price is $4 per million input tokens and $20 per million output tokens. This applies to the Carbon model intended for public access only.
API usage is billed separately and is not included in Google AI Plus, Pro or Ultra. Because Carbon uses more tokens than Argon, the same task can also cost more on the API. To estimate a task, plug your own input and output token counts into the token cost formula and example; for subscription prices by region, see AISub's Gemini price page, and confirm the final amount at checkout.
| Period | Input | Output |
|---|---|---|
| Introductory (through November 30, 2026) | $2 | $10 |
| After the introductory period | $4 | $20 |
Sources: Google: Gemini 4 Carbon is now available (November 10, 2026)Google: Gemini 4 Carbon is now available for developers
Frequently asked questions
Can Google AI Pro use Gemini 4 Carbon?
Not as of November 11, 2026. Google's announcement and the US subscriptions page list Carbon for Google AI Ultra only, and AI Pro keeps Gemini 4 Argon. Google has not said when, or whether, Carbon will reach AI Pro.
Sources: Google: Gemini 4 Carbon is now available (November 10, 2026)Google: Gemini subscriptions (Google AI Plus, Pro and Ultra)
Is there a Carbon difference between Ultra 5x and Ultra 20x?
Both tiers get Carbon. The difference is overall usage: the $99.99 tier gives 5x AI Pro and the $199.99 tier 20x, with higher and highest rate limits in Antigravity respectively. Google has not published a separate Carbon count.
Sources: Google: Gemini subscriptions (Google AI Plus, Pro and Ultra)Gemini Apps Help: Gemini Apps limits and upgrades for Google AI subscribers
Will Carbon use up my limits faster?
Usually, yes. Google says Carbon uses more tokens than Argon, and Gemini app limits are compute-based with the model as one factor. Limits refresh every five hours up to a weekly cap; after that you can continue with Flash-Lite.
Sources: Google: Gemini 4 Carbon is now available (November 10, 2026)Gemini Apps Help: Gemini Apps limits and upgrades for Google AI subscribers
What is the Gemini 4 Carbon API price?
Through November 30, 2026, $2 per million input tokens and $10 per million output tokens, the same as Argon; after that, $4 and $20. The API requires the paid tier and is not included in any Google AI plan.
Sources: Google: Gemini 4 Carbon is now available (November 10, 2026)Google: Gemini 4 Carbon is now available for developers
Can I use Carbon in Antigravity?
Google AI Ultra subscribers can use Carbon in the Antigravity desktop app, CLI and IDE extensions, and the /swarm preview is rolling out in the app and CLI. Google's announcement does not say AI Pro can use Carbon in Antigravity.
Sources: Google Antigravity Blog: Gemini 4 Carbon and /swarm (November 10, 2026)
Official sources and review notes
Sources checked on November 11, 2026. Rates and eligibility rules can change; confirm the latest official guidance and your own agreement.
- Google: Gemini 4 Carbon is now available (November 10, 2026)
- Google Antigravity Blog: Gemini 4 Carbon and /swarm (November 10, 2026)
- Google: Gemini 4 Carbon is now available for developers
- Google: Gemini subscriptions (Google AI Plus, Pro and Ultra)
- Gemini Apps Help: Gemini Apps limits and upgrades for Google AI subscribers
- Google Gemini on X: Gemini 4 Carbon rolling out to Google AI Ultra (November 10, 2026, 16:06 UTC)
This guide draws on the public sources listed below. Examples illustrate the calculation methods. AISub is an independent price index and is not affiliated with the product providers discussed.