Description: Gemini 4 Argon launched for consumers on October 13, 2026. Find out which Google AI subscriptions unlock it in the Gemini app, why Pro does not unlock it in Antigravity, and when API prices change.
Gemini 4 Argon is not included in the free Gemini app or Google AI Plus as of October 16, 2026. You can use it in the Gemini app with Google AI Pro or Ultra. For Argon inside Google Antigravity, the consumer subscription requirement is Ultra. The Gemini API follows a separate paid-developer route.
Which subscription unlocks which product?
| Where you want Argon | Free | AI Plus | AI Pro | AI Ultra |
|---|---|---|---|---|
| Gemini app and AI Mode in Search | No | No | Yes | Yes |
| Google Antigravity | No | No | No | Yes |
The Gemini API and Google AI Studio are a different billing route: Argon has no free API tier, and developers use a paid API tier. Paying for AI Pro in the consumer app is not a promise of free API calls. Likewise, the word “Pro” in a model name is not the name of your subscription.
What changed on October 13?
Google first described Argon on September 30 in the context of selected cybersecurity defenders. On October 13, 2026, it announced wider availability for developers, businesses and eligible paying consumers. Pro and Ultra subscribers gained access through the Gemini app and Search AI Mode; Ultra also gained the Antigravity route. Google describes a global rollout, so availability can still depend on your country, age, account and rollout status.
I pay for Pro. Why is Argon locked?
Check which product is showing the lock. In the Gemini chat app, Google lists AI Pro as eligible. In Antigravity, Google lists AI Ultra. In AI Studio or an API console, check your developer billing tier instead of the consumer subscription badge. If the app itself has not updated, verify your signed-in account and update the app before assuming your plan changed.
There is also no reliable fixed “Argon messages per day” figure in Google's general help. Usage depends on the complexity of a request and the features used. Allowances refresh every five hours until a weekly limit is reached. AI Pro has four times the standard allowance; Ultra offers five or twenty times Pro, depending on the subscription. Check Settings → Usage Limits in Gemini for your own remaining allowance and reset notice.
What happens to API pricing on December 1?
Through November 30, 2026, Argon costs $2 per million input tokens and $10 per million output tokens in the API. Starting December 1, those rates become $4 and $20. Output billing includes thinking tokens. This is an API price change, not a newly announced doubling of AI Pro's monthly subscription.
Bottom line: Choose AI Pro or Ultra for Argon in Gemini chat, Ultra for Argon in Antigravity, or a paid developer tier for API calls. A locked model is often a question of where you opened it, not simply whether you pay Google.
Official sources, checked October 16, 2026: Google launch announcement, October 13; Gemini API model and pricing, updated October 14; Gemini app limits and country eligibility. Search questions are editorial hypotheses, not measured search volumes by country.
