Google's Gemini 4 era is officially open for production. Gemini 4 Argon, announced September 30, reached Stable GA today, October 13, a brisk 13-day path from announcement to stable release.

Argon is the first Gemini 4 model and, importantly, the first built on a new pre-training run rather than an iteration of the Gemini 3 line. It follows Gemini 3.8 Flash (September 2) and a busy 2026 line that included Gemini 3.5 Flash and Gemini 3.1 Pro.

What Argon is, and is not

Argon is a GA foundation for the Gemini 4 family, not the whole family. Google's own positioning of Argon as the first Gemini 4 model all but confirms more tiers are coming, and our Gemini 4 Pro roundup tracks why a Pro tier is expected late this quarter.

Stable GA 13 days after announcement is a confident cadence. Google spent 2026 shipping Flash tiers; Argon says the flagship run is ready.

In the Model Guide, the Gemini family moves to Argon as its current model with an Adopt Now badge: Argon is complete and fully available, and only Pro-tier buyers gain anything by waiting for the family to fill out. Full comparison figures are in Reviews & Benchmarks.