Gemini 4 Argon Is Now in Google AI Pro: Do You Still Need AI Ultra at $99.99 a Month? (2026)

Two weeks ago, the only way to touch Gemini 4 Argon as a regular person was to pay for Ultra and then wait anyway.

That changed on October 13, 2026. 9to5Google reported that the Gemini app is rolling out Argon to both Google AI Pro and AI Ultra subscribers. Our October 3 guide on who could use Argon said Pro wasn’t on Google’s list. Now it is.

So if you’ve been paying $99.99 or more a month mainly to get the newest model, it’s worth asking whether you still need to. Here’s what Pro actually gets, what stays behind the Ultra paywall, and the math on each plan.

What You’ll Find Here

• Can Google AI Pro subscribers use Gemini 4 Argon now?
• How do you switch to Gemini 4 Argon in the Gemini app?
• Which Gemini 4 Argon features still need AI Ultra?
• Pro vs Ultra, Line by Line
• Is Google AI Ultra still worth paying for?
• Is the Gemini API a cheaper way to get Argon for coding?
• Argon Still Missing From Your Picker?
• Tips
• Warnings
• FAQ
• Sources

Can Google AI Pro subscribers use Gemini 4 Argon now?

Google AI Pro subscribers can use Gemini 4 Argon in the Gemini app and in AI Mode in Search, with a rollout that began on October 13, 2026, according to 9to5Google’s report on the expansion.

When Google announced Argon on September 30, access started with a small group of cyber defense partners. Google said paid API customers and AI Ultra subscribers would be next. Pro wasn’t mentioned at all.

That’s why this matters. Google’s U.S. subscription page now lists “Gemini 4 Argon” under AI Pro at $19.99 a month, right next to the Pro and Flash models.

One thing Google hasn’t published: how many Argon prompts a Pro subscriber gets before hitting a limit. The page says Pro has 4x the usage of the free tier overall. It doesn’t break that down per model. Anyone giving you an exact Argon prompt count for Pro is guessing.

How do you switch to Gemini 4 Argon in the Gemini app?

Gemini 4 Argon appears as “4 Argon” in the Gemini app’s model picker for AI Pro and AI Ultra subscribers, alongside 3.5 Flash-Lite, 3.8 Flash, and 3.1 Pro, according to 9to5Google’s October 13, 2026 report.

1. Update the app first. On Android or iPhone, install any pending Gemini app update. On the web, reload gemini.google.com.
2. Open a new chat. The model choice sits in the picker near the prompt box.
3. Choose 4 Argon. If you only see 3.1 Pro as the top option, your account isn’t in the rollout yet.
4. Check the new chat/tasks toggle. 9to5Google noted a toggle in the main chat window that switches between chat and tasks. Tasks is the feature Google previously called Spark.

On macOS, the Gemini app also lets you switch between chatting and coding, with direct access to Antigravity’s agentic coding interface. Keep reading before you rely on that part, though.

Which Gemini 4 Argon features still need AI Ultra?

Gemini 4 Argon in the Antigravity desktop app and CLI, in Google AI Studio, and in Android Studio (Canary) still requires a Google AI Ultra subscription as of October 13, 2026, per 9to5Google.

Google’s Gemini API pricing page backs this up from the other direction. It says Gemini 4 Argon “is not available on the Free tier or on the Google AI Pro plan.” So Pro gets Argon for chatting. It doesn’t get Argon as a developer tool.

This is where people will get tripped up.

Pro still includes Antigravity, but with what Google calls “entry rate limits.” That’s Antigravity running other models. Argon inside Antigravity’s desktop app and CLI is the Ultra part.

A few other things on the subscription page are Ultra-only too, and none of them have anything to do with Argon:

• Project Genie (the Genie 3 world model) is listed for Ultra only.
• Full Veo 3.1 video generation is Ultra. Pro gets a limited trial of Veo 3.1 Lite.
• Flow credits jump from 1,000 a month on Pro to 10,000 or 25,000 on Ultra.
• Storage goes from 5 TB on Pro to 20 TB and up on Ultra.

Pro vs Ultra, Line by Line

When I checked Google’s U.S. subscription page on October 14, 2026, I found that the two Ultra tiers are priced against Pro in an interesting way. The $99.99 tier gives 5x Pro’s usage at almost exactly 5x the price. The $199.99 tier gives 20x the usage at 10x the price.

Prices and features from Google’s U.S. Google AI subscription page and 9to5Google, checked October 14, 2026. “Extra cost per year” is our calculation: ($99.99 − $19.99) × 12 and ($199.99 − $19.99) × 12.

Put another way, the cheaper Ultra tier doesn’t give you any usage discount over Pro. You’re paying for the extra room and the developer access. The $199.99 tier is the only one where each unit of usage gets cheaper, roughly half the per-unit cost of Pro.

That’s only a deal if you’d actually use 20x what Pro allows. Most people won’t come close.

Is Google AI Ultra still worth paying for?

Google AI Ultra is still worth its $99.99 monthly starting price in 2026 mainly for people who need Gemini 4 Argon inside developer tools like Antigravity or AI Studio, or who regularly run into AI Pro’s usage limits, since Pro now includes Argon in the Gemini app.

Here’s how I’d sort it:

• You chat, write, research, and summarize: drop to Pro. You keep Argon in the app and save $80 a month.
• You hit Pro’s limits a few times a week during real work: the $99.99 tier makes sense. That’s what the 5x is for.
• You code with Argon in Antigravity or the CLI every day: you need Ultra. Pro can’t do it.
• You make a lot of video with Veo or Flow: the Flow credits alone may justify Ultra. 1,000 credits on Pro runs out fast.
• You’re not sure: try Pro for a month. If you never see a limit message, you have your answer.

If you’re also weighing Google against OpenAI and Anthropic at the $20 level, our ChatGPT Plus vs Claude Pro vs Google AI Pro comparison lines the three up. It was written before Argon reached Pro, so this rollout tilts the picture toward Google’s plan.

Is the Gemini API a cheaper way to get Argon for coding?

The Gemini API charges $2 per million input tokens and $10 per million output tokens for Gemini 4 Argon through November 30, 2026, rising to $4 and $20 on December 1, 2026, according to Google’s Gemini API pricing page.

So the gap between Pro and the cheaper Ultra tier, $80 a month, would buy about 8 million Argon output tokens at the current rate. After December 1, that same $80 buys about 4 million.

When I compared that with typical coding use, I noticed that the answer depends almost entirely on how much the model writes back. Output and thinking tokens are the expensive part. A light user who asks for a few fixes a day would likely spend far less than $80 on the API. A heavy user running long agent sessions could pass $80 in a week.

Two caveats from Google’s own page. Cached input is $0.10 per million through November 30, but it’s implicit caching only, with no explicit caching option. And there’s no free tier for Argon at all.

Honestly, if you write code for a living and use Antigravity daily, the flat Ultra price is easier to live with than a usage bill. If you code on weekends, the API is probably cheaper.

Argon Still Missing From Your Picker?

Google rolls these out in waves. If you’re on Pro and don’t see “4 Argon” yet, go through this short list.

1. Confirm your plan. Google AI Plus doesn’t include Argon. Plus lists only the Flash model on Google’s subscription page.
2. Check which account is signed in. If you have a personal Gmail and a work account, the subscription might be on the other one.
3. Check if it’s a Workspace account. 9to5Google’s report covers Google AI Pro and Ultra consumer plans. Workspace and Gemini Enterprise access can follow a different schedule set by your admin.
4. Update and sign out. Update the app, sign out, sign back in, then open a new chat.
5. Wait a few days. A staged rollout can take a week or more to reach every account.

Tips

• Before you downgrade from Ultra, check how much of your 20 TB-plus storage you’re using. Pro’s 5 TB is the ceiling after the switch.
• Use up remaining Flow credits before changing plans. Credits are tied to the plan you’re on.
• If you want to test Argon for coding before committing, the API’s pay-as-you-go pricing is a lower-risk trial than a month of Ultra.
• Note today’s API rates. They double on December 1, 2026, so any budget you set now needs a second look then.

Warnings

• Don’t assume your Pro subscription unlocks Argon in AI Studio or through an API key. Google’s pricing page says it doesn’t.
• Don’t trust third-party posts that list an exact number of Argon prompts per day on Pro. Google hasn’t published one.
• Older articles quote $249.99 a month for AI Ultra. That’s no longer the U.S. price on Google’s page.
• Prices here are U.S. prices. Google lists different prices by country, so check the page for your region before you switch.

FAQ

Can I use Gemini 4 Argon for free?

No. As of October 14, 2026, Gemini 4 Argon is not part of the free Gemini plan or Google AI Plus. You need Google AI Pro or AI Ultra in the Gemini app, or a paid Gemini API account, which has no free tier for Argon.

Does Google AI Pro include Argon in Google AI Studio?

No. Google’s Gemini API pricing page states that Gemini 4 Argon is not available on the Google AI Pro plan in that context. AI Studio and the Antigravity desktop app and CLI need AI Ultra, or a paid API key for direct API use.

Will the Gemini 4 Argon API price go up?

Yes. Google lists $2 per million input tokens and $10 per million output tokens through November 30, 2026. From December 1, 2026, the rates are $4 for input and $20 for output per million tokens.

Sources

• 9to5Google — Gemini app rolling out Gemini 4 Argon to AI Pro and AI Ultra (October 13, 2026)
• Google — Google AI Plus, Pro, and Ultra plans (U.S.)
• Google AI for Developers — Gemini API pricing

Fact-checked against Google’s subscription and Gemini API pricing pages and 9to5Google reporting as of October 14, 2026. Prices are U.S. list prices and can change; rollouts are gradual.