Google Releases Gemini 4 Hydrogen Model as New Default for AI Search

US tech giant Google announced on November 12, 2026, the release of its new Gemini 4 Hydrogen large language model, setting it as the default engine for its AI Mode search. Robby Stein, VP of Product at Google Search, described it as "the biggest model upgrade to Search yet." The model is available starting today across Search, the Gemini app, all tiers of Google AI Studio, the Gemini API, and Gemini for Business.

Google states that Gemini 4 Hydrogen is designed to provide more helpful answers to complex questions, including those with multiple parts, hard-to-understand typos, or highly specific requests. The new model can break down user questions and address each part in its responses. It also offers a wider range of links by "conducting simultaneous queries across all the relevant subtopics" and includes more visual elements like images, comparison tables, graphs, and maps. One example shared by Stein showed the AI generating an interactive animated driving simulation to explain how phones locate which lane of a highway a car is on in areas without cell service.

In terms of performance, Google claims Gemini 4 Hydrogen delivers "significant leaps in both speed and intelligence" compared to the previous Gemini Flash 3.8 model, and that it "matches or outperforms some of the competing models in its class," such as Anthropic's Claude Sonnet 5.5 and OpenAI's GPT-6.1 Terra. Users now have additional thinking level options, including low, medium, high, and a new "xhigh" mode. While these comparisons are based on Google's self-reported benchmarks and lack independent verification, the update marks the latest step in Google's deep integration of generative AI into its core search experience.