Gemini 1.5 Pro

Gemini 1.5 Pro, announced February 15, 2024 — just a week after Gemini 1.0 Ultra — made long context the story of 2024. Built on a mixture-of-experts architecture, it shipped with a 1M-token context window (later 2M), an order of magnitude beyond anything else available, and could ingest hour-long videos, entire codebases, or novels in a single prompt.

Its needle-in-a-haystack recall results forced every competitor to race toward longer contexts, and its Flash sibling (May 2024) built Google's reputation for aggressive price-performance. The 1.5 series carried Google's API lineup through 2024 via the -002 refresh before Gemini 2.0 opened the agentic era in early 2025.