Google: Gemini 3.1 Pro Preview

This row first appeared in OpenRouter's catalog on 2026-02-19source, accessed 2026-08-28 — confirmed against the model's own listing today, which still shows no non-preview release. That is more than six months before the snapshot of 31 August 2026 this page reads, and in all that time the tier has never shipped a plain row: the catalog, as observed on 31 August 2026, carried three Pro rows — this one, a batch billing tier, and a custom-tools variant — and every one of them still carried "preview" in its slug.

Its siblings didn't stay there. google/gemini-3.1-flash-lite-preview got its plain row 65 days after listing, and google/gemini-3.1-flash-image-preview got one 112 days after listing — and for the second of them graduation was not merely a change of slug: the plain row's context window is 131072tokensopenrouter-models, last checked 2026-09-14 against the preview's 65536tokensopenrouter-models, last checked 2026-09-14, which in the 31 August 2026 snapshot is twice the room at an unchanged input price. The Pro tier, heading at $2.00per million tokensopenrouter-models, last checked 2026-09-14 input — the top listed provider's rate for that row rather than necessarily Google's own — has had no such row at all.