Google says Gemini 4 is coming: what happened and why it matters

What happened: Google DeepMind chief executive Koray Kavukcuoglu said on 23 September that Gemini 4 has entered post-training — the safety-testing and fine-tuning stage before public release — and is already powering Google's internal Antigravity coding tool.

The timing: Google wants to release Gemini 4 well before the end of 2026, Kavukcuoglu said, though no firm date has been set.

The context: these were Kavukcuoglu's first public comments since taking over DeepMind's leadership in August, when Demis Hassabis stepped back to chair the unit and became Alphabet's chief scientist.

The background: Google's last flagship was Gemini 3 Pro in November 2025, followed by Gemini 3.1 Pro in February 2026. A Gemini 3.5 Pro model, announced at I/O in May, never shipped, per The Next Web.

The pause explained: Kavukcuoglu said Google eased off its flagship pace for a period to focus on smaller Flash models, including Gemini 3.8 Flash, released in September.

The competitive pressure: the comments follow Anthropic and OpenAI both launching new flagship models — Claude Opus 5.5 and GPT-6 Sol and Luna — on the same day, 22 September.

The quote: Kavukcuoglu said, "in my mind, it's a certainty that we are always gonna be at the frontier."

What's missing: Google has not published a model ID, pricing or model card for Gemini 4 yet, leaving key launch details unconfirmed.

Why it matters: the update is Google's clearest signal yet that a long-awaited flagship model is finally approaching release, after an earlier attempt, Gemini 3.5 Pro, stalled without shipping at all.

What is post-training: it's the stage after a model first learns from data, covering safety checks, behaviour guardrails and fine-tuning, and is usually the last major step before a public launch.

Internal testing: running Gemini 4 inside Antigravity gives Google real usage data ahead of launch, a normal step for a company this size before a wide public release.

The leadership angle: this is Kavukcuoglu's first public statement as DeepMind's chief, putting his own credibility behind Gemini 4's timeline as the company's new leader.

Unanswered: Google has not said how long post-training will take, or which products will get Gemini 4 first once it does launch.

The rival context: Anthropic and OpenAI have already shipped their newest flagships, leaving Google's own next major model as the one still to prove itself in public.

The prior stumble: a Gemini 3.5 Pro model, announced at Google's I/O event in May, was never actually released, making this the company's second attempt at a major flagship jump this year.

No firm date: Google described the target only as well before the end of 2026, without naming a month or quarter, so it should be read as intent rather than a confirmed schedule.