--- title: "Gemini 4 Argon joins AI Mode's model menu for Pro and Ultra" url: https://seomadman.com/news/gemini-4-argon-ai-mode-pro-ultra section: news language: en published: 2026-10-13T00:00:00.000Z modified: 2026-10-13T00:00:00.000Z author: Adam Hafez topics: ["AI search"] --- # Gemini 4 Argon joins AI Mode's model menu for Pro and Ultra ## The short answer Google added Gemini 4 Argon to AI Mode's model menu on 13 October 2026 for Google AI Pro and Ultra subscribers, selectable from the plus icon. Search Engine Journal reports that nothing announced changes the default for free users. If you track AI Mode answers, the model is now a variable to record. ## Key takeaways - Google added Gemini 4 Argon to the AI Mode model menu on 13 October 2026, and subscribers pick it from the plus icon. - Google's launch post lists both Google AI Pro and Ultra subscribers for AI Mode, while its first Argon post on 30 September did not mention Pro, per Search Engine Journal. - Search Engine Journal reports that nothing announced changes the default model for free-tier AI Mode users. - Anyone tracking AI Mode answers now has a model variable to log, because a paid account can run the same prompt on Argon or on another listed model. - Neither Google's post nor Robby Stein's announcement says whether Argon will stay an option or become the default. Google has added Gemini 4 Argon to the AI Mode model menu for Google AI Pro and Ultra subscribers. Robby Stein, Google's VP of Product for Search, announced it on X, and Search Engine Roundtable credits Nick Fox as well. Both reports quote the line that Argon is "now rolling out globally in Search". Google's own post, [Gemini 4 Argon: Built to solve your hardest problems](https://blog.google/innovation-and-ai/models-and-research/gemini-models/introducing-gemini-4-argon/), is dated 13 October 2026. ## What did Google add to AI Mode? A new entry in the model menu. Per [Search Engine Journal](https://www.searchenginejournal.com/google-gemini-4-argon-ai-mode/592806/), subscribers pick Argon from the plus icon in AI Mode's Ask anything bar, the same menu that [gained 3.7 Flash in August](/news/gemini-3-7-flash-ai-mode). Stein describes it as bringing "big improvements to tackling nuanced, multi-step tasks" and being better at following instructions in back and forth conversations, per both reports. Google's launch post makes a broader claim for the model: that it follows style instructions better than any previous Gemini model. ## Who can pick Gemini 4 Argon? Paid subscribers. Google's launch post says the model is available in the Gemini app and AI Mode in Search for Google AI Ultra and Pro subscribers. It lists developers and enterprises through the API, and Ultra subscribers in Google Antigravity, as separate groups. Search Engine Journal notes that Google's first Argon post, on 30 September, did not mention Pro subscribers and said the release would start with paid API customers and Ultra subscribers. It also reports the rollout had not reached the menu on its writer's own Pro account at 12:17 p.m. ET, so availability may vary at first. Neither Google's post nor Stein's announcement states a language, per that report. ## Does the default model change? Not according to the reports. Search Engine Journal says nothing announced on 13 October changes the default for free-tier AI Mode users, and describes Argon as subscription only, like the two Flash models that joined the menu before it. Google's support page for the model menu still named only "Pro" and "Fast" when that outlet read it on the day. We did not check the page ourselves. ## How do you test AI Mode answers? Treat the model as a variable. Google has not published anything about how Argon changes sourcing or citations, so a different answer from the same prompt may reflect the model, not a change to your page. If you track AI Mode answers from a paid account, record which model produced each one. Search Engine Journal suggests a simple check once Argon appears in your menu: run the same multi-step sequence with follow-up questions on Argon and on 3.8 Flash if it is still listed, and note which model answers each time. Search Engine Roundtable embeds a post from Gagan Ghotra saying links appear in Argon's AI Mode responses this time, unlike the 3.8 Flash release. We have not verified that claim. ## What is still unknown? Whether Argon stays an option or becomes the default. Search Engine Journal points out that two earlier Flash models launched as the default while Gemini 3 Pro launched as an option and has stayed one, and that neither Google's post nor Stein's says which path Argon takes. The same outlet adds that Google's post only promises "the rest of the Gemini 4 family" without saying which models reach AI Mode. For the wider picture of how these features fit together, see the [AI search](/topics/ai-search) hub. ## Frequently asked questions ### Who can use Gemini 4 Argon in AI Mode? Google AI Pro and Ultra subscribers. Search Engine Roundtable and Search Engine Journal both describe it as an option for paid subscribers, chosen from the plus icon in AI Mode's Ask anything bar. ### Did the default AI Mode model change? Search Engine Journal reports that nothing announced on 13 October changes the default for free-tier AI Mode users. Argon is an option in the menu, not a replacement. ### Does Argon change how AI Mode picks sources? Google's description covers multi-step tasks, following instructions and style, not sourcing or citations. No change to how AI Mode selects pages was announced. ## Sources 1. [Gemini 4 Argon: Built to solve your hardest problems](https://blog.google/innovation-and-ai/models-and-research/gemini-models/introducing-gemini-4-argon/) - Google (primary) 2. [Gemini 4 Argon: our next era of frontier intelligence](https://blog.google/innovation-and-ai/models-and-research/gemini-models/gemini-4-argon/) - Google (primary) 3. [Google Adds Gemini 4 Argon To AI Mode For Pro & Ultra Subscribers](https://www.searchenginejournal.com/google-gemini-4-argon-ai-mode/592806/) - Search Engine Journal 4. [Gemini 4 Argon In Google Search Via AI Mode](https://www.seroundtable.com/google-ai-mode-gemini-4-argon-42289.html) - Search Engine Roundtable