What to know first
If you are on the free plan, leave auto model selection on, or every reply will use Flash-Lite. If you are on AI Plus, Hydrogen is the most capable model the plan's subscriptions page now lists, but Plus still has a 128K-token context window and 2x the standard limits. Upgrading to AI Pro gets you Argon, Hydrogen in Tasks and Antigravity, and a 1M-token context window, not more Hydrogen in chats alone. Developers can test Hydrogen on the API free tier first; the paid price is double Gemini 3.8 Flash's current introductory price, and the same as 3.8 Flash's price from January 1, 2027.
What did Google release on November 12?
Google's blog post "Introducing Gemini 4 Hydrogen", dated November 12, 2026, describes Hydrogen as a fast, efficient model for everyday coding and agentic work, sitting below the frontier models Gemini 4 Carbon and Gemini 4 Argon. Google says Hydrogen scores 51 on the Artificial Analysis Intelligence Index at its default high thinking level, against Argon's 50, and 54 at its highest xhigh setting. These are Google's published figures, not a guarantee for your own tasks.
The official Google AI X account listed where it is available in a post on November 12 at 18:03 UTC (November 13, 02:03 Singapore time): the Gemini app and Google Search for all users, Gemini in Google Sheets for AI Pro and Ultra, and Google Antigravity for paid AI Pro and Ultra. The Google Gemini X account added three minutes later that the rollout covers desktop, mobile and web globally, and that free users get Hydrogen through auto model selection.
| Item | What Google says |
|---|---|
| Release date | November 12, 2026 (November 13, Singapore time) |
| Gemini app | Rolling out to all users; free users only through auto model selection |
| Google Search | All users |
| Gemini in Google Sheets | Google AI Pro and Ultra |
| Google Antigravity | Paid Google AI Pro and Ultra subscribers |
| Gemini API | Free tier and paid tier: $1.50 input / $7.50 output per million tokens |
| Plan prices | No price change announced |
Sources: Google: Introducing Gemini 4 Hydrogen (November 12, 2026)Google AI on X: where Gemini 4 Hydrogen is available (November 12, 2026, 18:03 UTC)Google Gemini on X: Gemini 4 Hydrogen rollout and free-user access (November 12, 2026, 18:06 UTC)
Which Google AI plans can choose Gemini 4 Hydrogen?
The Gemini Help Center article "About Gemini models", checked on November 13, 2026, lists models by plan. Without a plan, chats use "Auto or Flash-Lite": with auto model selection on, most prompts use Flash-Lite and prompts that need more reasoning may use Hydrogen; with it off, every reply uses Flash-Lite. AI Plus lists Flash-Lite, Hydrogen and Pro for chats and no Tasks. AI Pro lists Flash-Lite, Hydrogen, Pro and Argon for chats, plus Hydrogen and Argon in Tasks. AI Ultra lists Flash-Lite, Hydrogen, Argon and Carbon for chats, plus Hydrogen, Argon and Carbon in Tasks.
Usage still follows the Gemini limits page: AI Plus gets 2x the standard limits, AI Pro 4x, and Ultra 5x or 20x AI Pro depending on the tier. Limits are compute-based, refresh every five hours until you reach the weekly limit, and Google says more advanced models and higher thinking levels use more of your usage. Google has not published a Hydrogen-specific count for any plan. For full plan prices and regional prices, see Google AI Plus vs Pro vs Ultra.
| Plan (US monthly price) | Hydrogen in chats | Hydrogen in Tasks | Usage multiple | Context window |
|---|---|---|---|---|
| Free ($0) | Only through auto model selection | No | Standard limits | 32K tokens |
| AI Plus ($4.99) | Yes, can pick it | No | 2x standard | 128K tokens |
| AI Pro ($19.99) | Yes | Yes | 4x standard | 1M tokens |
| AI Ultra ($99.99) | Yes (highest access) | Yes | 5x AI Pro | 1M tokens |
| AI Ultra ($199.99) | Yes (highest access) | Yes | 20x AI Pro | 1M tokens |
Sources: Gemini Apps Help: About Gemini modelsGoogle: Gemini subscriptions (Google AI Plus, Pro and Ultra)Gemini Apps Help: Gemini Apps limits and upgrades for Google AI subscribers
What does Hydrogen change for Google AI Plus subscribers?
On the US subscriptions page checked on November 13, 2026, the AI Plus card now reads "Access to Gemini 4 Hydrogen" and is badged "Includes Gemini 4 Hydrogen"; it does not list the Pro model. The AI Pro card lists Gemini 4 Argon, "Access to our Pro model" and Gemini 4 Hydrogen. The Help Center model table, checked the same morning, still shows Pro under AI Plus chats. The two official pages disagree, so check the model picker in your own account to see whether Pro is still there.
What Plus does not change: the context window is still 128K tokens (AI Pro has 1M), usage is still 2x the standard limits (AI Pro is 4x), and Tasks, Argon and Antigravity's Hydrogen access are not part of Plus. If you mainly upload long PDFs or large sets of files, the context gap matters more than the model name. You can compare App Store prices for AI Plus and AI Pro by region on AISub's Gemini price page.
| Item | AI Plus | AI Pro |
|---|---|---|
| Monthly price (US) | $4.99 | $19.99 |
| Gemini 4 Hydrogen in chats | Yes | Yes |
| Gemini 4 Argon | No | Yes |
| Pro model | Not listed on the subscriptions page; still listed in the Help Center table | Yes |
| Tasks | No | Hydrogen and Argon |
| Context window | 128K tokens | 1M tokens |
| Usage multiple | 2x standard | 4x standard |
Sources: Google: Gemini subscriptions (Google AI Plus, Pro and Ultra)Gemini Apps Help: About Gemini modelsGemini Apps Help: Gemini Apps limits and upgrades for Google AI subscribers
Hydrogen in Antigravity and Sheets: which plans get it?
The Antigravity blog says Hydrogen is rolling out across paid Google AI Pro and Ultra subscriptions in Google Antigravity. When you pick Hydrogen directly, you can choose four thinking levels: low, medium, high (the default) and a new xhigh. Antigravity also adds Orchestrator, which lets Gemini 4 Carbon plan and hand routine steps such as edits, package updates and test runs to Hydrogen. On Terminal-Bench 4.1, Google says Orchestrator came close to Carbon's success rate while using 24% less quota and finishing 19% faster on average.
Google does not state a separate plan requirement for Orchestrator. Carbon itself was opened in Antigravity only to AI Ultra on November 10; see which plans get Gemini 4 Carbon. Hydrogen in Gemini in Google Sheets is listed for AI Pro and Ultra. To compare Antigravity with Codex and Claude Code at each price point, see Codex vs Claude Code vs Antigravity.
| Surface | Who can use Hydrogen |
|---|---|
| Gemini app chats | All users (free only through Auto) |
| Gemini app Tasks | AI Pro and Ultra |
| Google Search | All users |
| Gemini in Google Sheets | AI Pro and Ultra |
| Google Antigravity | Paid AI Pro and Ultra |
| Orchestrator in Antigravity | Plan requirement not stated; Carbon in Antigravity is Ultra only |
Sources: Google Antigravity Blog: Gemini 4 Hydrogen and Orchestrator (November 12, 2026)Google: Introducing Gemini 4 Hydrogen (November 12, 2026)Google AI on X: where Gemini 4 Hydrogen is available (November 12, 2026, 18:03 UTC)
How much does the Gemini 4 Hydrogen API cost?
On the Gemini API pricing page checked on November 13, 2026, Hydrogen's standard paid price is $1.50 per million input tokens and $7.50 per million output tokens (output includes thinking tokens), flat across its 1M-token context window. Batch and Flex are $0.75 and $3.75, and Priority is $2.70 and $13.50. Hydrogen also has a free tier on the API, while the same page says Gemini 4 Argon and Gemini 4 Carbon are not available on the free tier.
For comparison, Gemini 3.8 Flash is listed at $0.75 and $3.75 through December 31, 2026, and $1.50 and $7.50 from January 1, 2027. By AISub's arithmetic, Hydrogen's standard price is twice 3.8 Flash's current price and equal to its 2027 price. API usage is billed separately and is not included in any Google AI plan. To estimate a task, plug your own token counts into the token cost formula and example.
| Model | Input | Output | Free tier |
|---|---|---|---|
| Gemini 4 Hydrogen | $1.50 | $7.50 | Yes |
| Gemini 4 Hydrogen (Batch / Flex) | $0.75 | $3.75 | No |
| Gemini 3.8 Flash (through Dec 31, 2026) | $0.75 | $3.75 | Yes |
| Gemini 3.8 Flash (from Jan 1, 2027) | $1.50 | $7.50 | Yes |
| Gemini 4 Argon (through Nov 30, 2026) | $2.00 | $10.00 | No |
| Gemini 4 Argon (from Dec 1, 2026) | $4.00 | $20.00 | No |
Sources: Google AI for Developers: Gemini API pricingGoogle: Introducing Gemini 4 Hydrogen (November 12, 2026)
Frequently asked questions
Can free Gemini users use Gemini 4 Hydrogen?
Only indirectly. Free users cannot pick Hydrogen; with auto model selection on, most prompts use Flash-Lite and prompts that need more reasoning may use Hydrogen. With auto model selection off, every reply uses Flash-Lite.
Sources: Gemini Apps Help: About Gemini modelsGoogle Gemini on X: Gemini 4 Hydrogen rollout and free-user access (November 12, 2026, 18:06 UTC)
Can Google AI Plus choose Hydrogen manually?
Yes. As of November 13, 2026, the Help Center lists Hydrogen among AI Plus chat models and the US subscriptions page lists "Access to Gemini 4 Hydrogen" for AI Plus at $4.99 a month. Tasks are not included in Plus.
Sources: Gemini Apps Help: About Gemini modelsGoogle: Gemini subscriptions (Google AI Plus, Pro and Ultra)
Do I need to upgrade to AI Pro for Hydrogen?
Not for chats, since AI Plus can pick it. AI Pro adds Argon, Hydrogen in Tasks, Antigravity and Sheets, a 1M-token context window and 4x the standard limits, at $19.99 a month in the US.
Sources: Gemini Apps Help: About Gemini modelsGoogle: Gemini subscriptions (Google AI Plus, Pro and Ultra)Gemini Apps Help: Gemini Apps limits and upgrades for Google AI subscribersGoogle AI on X: where Gemini 4 Hydrogen is available (November 12, 2026, 18:03 UTC)
Does Hydrogen use up my Gemini limits faster?
Google has not published a Hydrogen-specific count. Its Help Center says limits are compute-based and that more advanced models and higher thinking levels use more of your usage. When a subscriber hits the limit, chats continue with Flash-Lite.
Sources: Gemini Apps Help: About Gemini modelsGemini Apps Help: Gemini Apps limits and upgrades for Google AI subscribers
What does the Gemini 4 Hydrogen API cost?
$1.50 per million input tokens and $7.50 per million output tokens on the standard paid tier, $0.75 and $3.75 on Batch or Flex, and there is a free tier. API usage is billed separately from Google AI plans.
Sources: Google AI for Developers: Gemini API pricingGoogle: Introducing Gemini 4 Hydrogen (November 12, 2026)
Official sources and review notes
Sources checked on November 13, 2026. Rates and eligibility rules can change; confirm the latest official guidance and your own agreement.
- Google: Introducing Gemini 4 Hydrogen (November 12, 2026)
- Google Antigravity Blog: Gemini 4 Hydrogen and Orchestrator (November 12, 2026)
- Gemini Apps Help: About Gemini models
- Google: Gemini subscriptions (Google AI Plus, Pro and Ultra)
- Gemini Apps Help: Gemini Apps limits and upgrades for Google AI subscribers
- Google AI for Developers: Gemini API pricing
- Google Gemini on X: Gemini 4 Hydrogen rollout and free-user access (November 12, 2026, 18:06 UTC)
- Google AI on X: where Gemini 4 Hydrogen is available (November 12, 2026, 18:03 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.