"Gemini CLI" gets new model "Gemini 3 Flash" — 3x faster and under a quarter of the cost of 2.5 Pro
On December 17, 2025, Google announced that the new model “Gemini 3 Flash” was now available in “Gemini CLI.” It scored 78% on SWE-bench Verified, a benchmark for agentic coding, surpassing both the higher-tier Gemini 3 Pro and the earlier 2.5 series, while running 3x faster than 2.5 Pro at under a quarter of the cost — a standout balance of performance and efficiency.
Details
- Performance: Scored 78% on SWE-bench Verified, achieving a higher score than not only the 2.5 series but also Gemini 3 Pro
- Speed and cost: Costs under a quarter of Gemini 3 Pro while running 3x faster than 2.5 Pro, positioned as well-suited to the high-frequency back-and-forth common in terminal work
- Supported tasks: Now capable of tasks that previously required a Pro-class model, such as generating 3D graphics and analyzing code with large context
- Availability: Available to Gemini CLI users, paid Google AI Pro/Ultra subscribers, and paid API key users. Rollout to free-tier users is proceeding gradually
- How to enable it: Update to Gemini CLI version 0.21.1 or later, enable “preview features” in settings, then select Gemini 3 from the model selection menu
- Automatic routing: Also includes a mechanism that automatically routes complex tasks to Gemini 3 Pro and everyday work to Flash
What happened next
Adding Gemini 3 Flash marked an important step in Gemini CLI’s evolution into an established practical tool. That said, half a year later, in May 2026, Google announced that Gemini CLI itself would be folded into its new platform “Antigravity,” marking a major turning point as individual-focused availability came to an end.