Image: Google

Google is bringing Gemini 4 Argon, its most powerful AI model, to Antigravity for people who pay for Google AI Pro. Until now, the cheaper Pro plan got Argon in the Gemini app but not in Antigravity, Google's app where AI agents write, test and fix code for you. In Antigravity, it was for Ultra and business customers only.

The catch is a new limit. Google says Pro subscribers get a separate, "weekly-only" Argon allowance on top of their existing Gemini 3.8 Flash quota.

We’re rolling out Gemini 4 Argon in Antigravity to paid Google AI Pro subscribers today. Demand has been incredible and we've scaled capacity deliberately to get here. We’ve rolled out a separate weekly-only Argon quota for Pro on top of the existing Gemini bucket for 3.8 Flash so you have the best of Gemini for all your tasks.

— Google Antigravity (@antigravity) October 15, 2026

The change came fast. Google's launch post limited Antigravity access to Ultra subscribers. As recently as this week, a reply on Google's developer forum said there was no timeline for Pro. Google says it held back to add server capacity first, and it hasn't said how big the new weekly allowance is.

That allowance works differently from the rest of the plan. Google's plans page says Pro quota normally refills every five hours until you hit a weekly cap. A weekly-only Argon quota suggests there's no five-hour top-up: once it's gone, you wait for the reset or pay for extra AI credits. Google also says heavier, more complex tasks use up quota faster than simple ones.

Not every Pro subscriber qualifies. Antigravity's model docs say Argon on Pro is for "non-trial subscriptions only," and free and AI Plus users don't get it. That matters in India, where many people have Pro through Jio's 18-month offer. The forum reply describes that bundle as a promotional, extended-trial membership, so those users probably won't see Argon. Google hasn't confirmed that directly.

For Pro users, this is still a real upgrade. The same docs show Gemini 3.1 Pro is no longer offered on consumer plans, which left Gemini 3.8 Flash as Pro's best Gemini option in Antigravity until now.

Google's Antigravity blog claims more than 100,000 people across Alphabet use Argon in an internal version of the tool each month. It credits Argon with a 30% drop in code changes that had to be rolled back. Those are Google's own figures and haven't been independently checked. Some Pro users have also complained that Argon's limits in the Gemini app run out quickly.

How to get the most from Argon in Antigravity

• Update Antigravity, then pick Gemini 4 Argon from the model menu under the prompt box. It's in the Antigravity app, the CLI and the IDE extensions, but not in the separate Antigravity IDE.
• Save Argon for hard jobs like tricky bugs, big refactors or planning. Use Gemini 3.8 Flash, which has its own quota, for routine edits.
• Check how much you have left. The model menu shows your remaining weekly allowance, and Settings shows usage across models.
• To avoid surprise charges, set AI Credit Overages to "Never" in Settings. Antigravity will then wait for your quota to reset instead of spending paid credits.