Ways to buy 6
| Way to buy | Input | Output | In / out per 1M | Cached | Vs list |
|---|---|---|---|---|---|
 Google Vertex AIglobal-flex, cheapest · cached $0.1 | $1 | $6 | $1 / $6-50% vs list | $0.1 | -50% vs list |
 Google Gemini APIflex · cached $0.1 | $1 | $6 | $1 / $6-50% vs list | $0.1 | -50% vs list |
| Google Gemini API API The lab's own API · cached $0.2 | $2 | $12 | $2 / $12List price | $0.2 | List price |
| Google Vertex AI global · cached $0.2 | $2 | $12 | $2 / $12Same as list | $0.2 | Same as list |
| Google Vertex AI global-priority · cached $0.36 | $3.6 | $21.6 | $3.6 / $21.6+80% vs list | $0.36 | +80% vs list |
| Google Gemini API priority · cached $0.36 | $3.6 | $21.6 | $3.6 / $21.6+80% vs list | $0.36 | +80% vs list |
USD per 1M tokens; batch $1 in, $6 out on the lab's API. Regions are separate routes.
Through a gateway
Your own numbers100M input and 20M output tokens a month: $440.00 direct.
Helicone$440.00+0%
Kong AI Gateway$440.00+0%
LiteLLM$440.00+0%
Vercel AI Gateway$440.00+0%
Cloudflare AI Gateway$462.00+5%
Requesty$462.00+5%
Eden AI$464.20+5.5%
OpenRouter$464.20+5.5%
No published token fee: Martian Gateway, Portkey, TrueFoundry AI Gateway.
Related models
| In / out per 1M | Cheapest route | ||||||
|---|---|---|---|---|---|---|---|
| Gemini 3.8 Flash Google · 1MCheapest: $0.75 on Google Gemini API (flex) | $0.75 | $3.75 | $0.75 / $3.75 | $1.5 | 1M | $0.75 on Google Gemini API (flex) | · |
| Gemini 3.7 Flash Google · 1MCheapest: $0.75 on Google Vertex AI (global-flex) | $0.75 | $3.75 | $0.75 / $3.75100% | $1.5 | 1M | $0.75 on Google Vertex AI (global-flex) | 100% |
| Gemini 3.5 Flash Lite Google · 1MCheapest: $0.425 on Google Vertex AI (global-flex) | $0.3 | $2.5 | $0.3 / $2.5 | $0.85 | 1M | $0.425 on Google Vertex AI (global-flex) | · |
| Gemini 3.6 Flash Google · 1MCheapest: $0.75 on Google Vertex AI (global-flex) | $0.75 | $3.75 | $0.75 / $3.75 | $1.5 | 1M | $0.75 on Google Vertex AI (global-flex) | · |
 Claude Opus 5Anthropic · 1M | $5 | $25 | $5 / $25 | $10 | 1M | Lab list price | · |
| Claude Opus 5.5 Anthropic · 1M | $4 | $20 | $4 / $20 | $8 | 1M | Lab list price | · |
 GPT-5.6 SolOpenAI · 1.05MCheapest: $2 on OpenAI (flex) | $2 | $10 | $2 / $10 | $4 | 1.05M | $2 on OpenAI (flex) | · |
| Claude Opus 4.6 Anthropic · 1M | $5 | $25 | $5 / $25 | $10 | 1M | Lab list price | · |
About Gemini 3.1 Pro Preview
Gemini 3.1 Pro Preview is Google’s frontier reasoning model, delivering enhanced software engineering performance, improved agentic reliability, and more efficient token usage across complex workflows.
Takes audio, files, image, text, video in and returns text. First listed Mar 3, 2026. Up to 66K output tokens. Blended price $4.5 per 1M tokens at 3 input to 1 output. Overall score 15 on leadersboard.fru.dev (rank 14). Model id gemini-3-1-pro-preview.
Price history
List price since Mar 3, 2026, from Internet Archive snapshots of the OpenRouter catalog, then daily reads.
Across fru.devCompany profile7 acquisitionsPay schedule7 conferences
Questions
How much does Gemini 3.1 Pro Preview cost?
$2 per million input tokens and $12 per million output tokens, with cached input at $0.2, or $1 and $6 through the Batch API.
What is the context window of Gemini 3.1 Pro Preview?
1M tokens, with up to 66K tokens of output.
Where is Gemini 3.1 Pro Preview cheapest?
Of 6 routes tracked, Google Vertex AI is cheapest at $1 input and $6 output per million tokens.
Sources: OpenRouter's public model catalog and each provider's own pricing page, read every morning at 05:00 UTC; gateway fees re-read every Monday. List prices: your contract may differ. Logos via logo.dev; trademarks belong to their owners.