Gemini 4 Hydrogen: What free users and Google AI Plus get

Google released Gemini 4 Hydrogen on November 12 and is rolling it out worldwide in the Gemini app, Google Search and the Gemini API. Hydrogen replaces Gemini 3.8 Flash as Google's everyday model and is the first of these models to drop the Flash name. According to Google's announcement, it finishes tasks 2.5 times faster than its predecessor and makes fabricated claims more than five times less often. On the Artificial Analysis Intelligence Index it scores 51, one point ahead of the larger Gemini 4 Argon.

Google AI Plus now leads with Hydrogen

Paying subscribers see the biggest change. On Google's Gemini plans page, Google AI Plus at $4.99 per month now lists Gemini 4 Hydrogen as its headline model, along with twice the usage limits of the free tier. The Pro model no longer appears in the Plus column. It starts with Google AI Pro at $19.99, which also includes Gemini 4 Argon. Google had told Plus subscribers by email that they would lose the Pro models on November 13, as we reported. Google's help page on Gemini models still lists Pro under AI Plus, so the two pages currently disagree.

Free users depend on auto model selection

Free users cannot pick Hydrogen themselves. Google says they get it through auto model selection "when it's the appropriate model for the prompt." The Gemini Apps Help adds that most prompts still go to Flash-Lite and that "prompts that require more reasoning may use Hydrogen." With auto model selection turned off, every reply comes from Flash-Lite. That has been the only model free users can select manually since October, as we covered.

You can check which model wrote a reply. On gemini.google.com, open the menu below a response, choose Show thinking steps and scroll to the bottom, where Gemini names the model it used. The switch for auto model selection is under Settings and Usage limits.

Search and the API get Hydrogen too

Google says Hydrogen is available in Google Search for all users worldwide and handles multi-part questions and typos better. Developers pay $1.50 per million input tokens and $7.50 per million output tokens across the full context window of 1 million tokens. The model offers four thinking levels, including a new xhigh setting for the most thorough answers. Our comparison of ChatGPT, Gemini and Claude plans shows what the major AI subscriptions cost.