Gemini 3.1 Pro (preview)
Gemini 3.1 Pro (preview) is Google's most capable Gemini model as of late July 2026, served as gemini-3.1-pro-preview. It achieves a world-record 94.3% on GPQA Diamond, 77.1% on ARC-AGI-2, and 94 on BenchLM, but still carries the -preview suffix and has no free tier.