Gemini Reasoning Verified 19 Aug 2026

Gemini 3.1 Pro

Stable, capable reasoning — a dependable production choice.

Maker: Google
Context: Very large (1M+ tokens)
Pricing: $2 / 1M tokens / $12 / 1M tokens

Prompts over 200k tokens are re-rated to $4 / $18. Still listed as "Preview" on Google's pricing page.

Best for

Complex problem-solving where a simple answer isn't enough
Production workflows that value stability over the newest release
Advanced reasoning on hard, well-specified tasks

Prompting quirks

Still the Pro tier you can actually use

3.5 Pro remains in testing, so if you need Google's reasoning tier in production today, this is it. New flagships churn; a stable prior-gen Pro is often the smart call.

Be explicit about depth

Tell it when you want thorough reasoning vs. a quick answer — it'll match the effort to your stated need.

Copy-paste example

Tuned for Gemini 3.1 Pro. Swap in your own content where marked.

Opportunity-solution mapping

Here are our validated discovery findings:
{paste findings}
Map these into an opportunity-solution tree: the top opportunities, and
2–3 candidate solutions under each. Flag which solutions are assumptions
we haven't tested.

Facts verified against the official Google docs on 19 August 2026.