Google Quietly Upgrades to Gemini 3.6 Flash After 3.5 Fell Short on Coding

Key points

• Google released three new AI models in mid-2025, including an updated Gemini 3.6 Flash and its first AI model built specifically for cybersecurity.
• Gemini 3.5 Flash, announced with fanfare at Google I/O in May 2025, has already been deprecated, meaning it is switched off and no longer available to use.
• Gemini 3.5 Pro, which Google said would launch in June 2025, remains unreleased and is still in testing.
• Google says 3.6 Flash improves on coding and multimodal tasks, the ability to understand and work with text, images and other formats at once, based on user feedback.

Google does not always wait long before replacing its own products. Gemini 3.5 Flash, the centrepiece of the company's big I/O developer conference just weeks ago, is already gone. In its place sits Gemini 3.6 Flash, a large language model, meaning the same kind of AI technology that powers chatbots like ChatGPT.

The version jump is small on paper. Google says 3.6 Flash is marginally more capable, better at writing and checking code, and handles multimodal tasks more reliably. The company frames the changes as a direct response to complaints from developers who found that 3.5 Flash did not deliver on Google's coding promises.

That criticism matters. Coding tasks are one of the clearest ways businesses measure whether an AI model is worth paying for. If a model stumbles there, companies notice quickly.

Also in the batch of new releases: Google's first Gemini model aimed at cybersecurity, the practice of protecting computer systems and data from attacks. Details on that model remain sparse, but its existence signals Google is pushing into a market where rivals like Microsoft already have dedicated security AI products.

What is conspicuously absent is Gemini 3.5 Pro, which Google had pencilled in for a June launch. As first reported by Ars Technica AI, that model is still in testing with no firm release date.

Why does a version number change matter to ordinary users?

If you use Google's AI tools through products like Google Workspace or the Gemini app, you likely will not feel a jarring switch. The upgrade happens in the background. What you might notice is slightly better results when asking the AI to help write, summarise or check documents.

Developers who built apps on top of Gemini 3.5 Flash are in a different position. Deprecated means the old version is gone, so any application still pointing at 3.5 Flash needs updating now.

For everyone else, the bigger story is what Google has not shipped. Gemini 3.5 Pro was expected to be the company's most capable model in this line. Its delay, combined with the rapid retirement of 3.5 Flash, suggests Google is under pressure to balance raw performance against cost. Running powerful AI models is expensive, and businesses are increasingly pushing back on high per-query fees.

Google has not announced a new launch window for 3.5 Pro.