Gemini 4 Argon is generally available
Google's frontier model for hard coding, science, and agent work is now in the API and for AI Pro and Ultra subscribers.
Official source (opens in a new tab)
Google says Gemini 4 Argon (gemini-4-argon) is generally available as of 13 October 2026. The Gemini API changelog calls it the most capable Gemini model for complex coding, agentic, math, and science tasks. The launch post says the API has a 1 million token input-output limit, with an introductory price of $2 per million input tokens and $10 per million output tokens through 30 November 2026, then $4 and $20. Cached input is 95% off during that introductory period.
Who it's for: developers and enterprises on the paid Gemini API, and Google AI Pro and Ultra subscribers in the Gemini app and AI Mode in Search. Ultra subscribers can also try it in Google Antigravity.
Fits: Best for Research, and the coding half of Best for Vibe Coding when the job is a hard problem rather than an in-editor edit.