Long context

gemini-3.1-pro-preview API pricing

Google's Gemini series — very long context windows and strong multimodal input.

Model IDgoogle/gemini-3.1-pro-preview

ChatStreamingTool callingVision

Get API Key Run your first request

Call summary

Input

$2.00$0.20/ 1M tokens

Cache write $0.20

Output

$12.00/ 1M tokens

Cache read $0.20

Context Window

1.05M

API Endpoints

Available Configurations

gemini-3.1-pro-preview API endpoints

One API key — this model is served on the endpoint below.

POST/v1/chat/completionsOpenAI-compatible · Works for every model

Docs

Production reliability

Privacy-safe aggregates from real Router One model calls, so you can assess stability and response latency before integrating.

Successful response share

88.37%

Success 2xx

88.37%

Rate limit 429

2.33%

Server 5xx

9.30%

TPS

—

tokens/s

Avg. time to first token

—

Avg. latency

39.77 s

Includes production requests ending in 2xx, 429, or 5xx. Average latency uses successful requests; time to first token and TPS require complete observations from successful streams. Public thresholds are 100 requests and 5 independent principals.

Updated Sep 10, 2026, 10:51 PM UTC

More Gemini models on Router One

11 other Gemini models on the same gateway and API key — each page lists endpoints, posted price, and context window.

Call gemini-3.1-pro-preview from your code

Your API key works on this endpoint.

Endpoint

/v1/chat/completions

Model ID

google/gemini-3.1-pro-preview

Routing mode

auto

Request example

bash

curl -X POST \
  https://api.router.one/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "model": "google/gemini-3.1-pro-preview",
    "messages": [
      {"role": "user", "content": "Hello!"}
    ]
  }'

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gemini-3.1-pro-preview at a glance

gemini-3.1-pro-preview is a Gemini-series text model on Router One. Posted rate: $0.20 in / $12.00 out per 1M tokens (was $2.00 in / $12.00 out). Context window: 1.05M tokens. Accepts text, image; returns text. Endpoint: POST /v1/chat/completions (OpenAI-compatible).

gemini-3.1-pro-preview FAQ

How much does gemini-3.1-pro-preview cost on Router One?

gemini-3.1-pro-preview is billed per token on Router One: $0.20 in / $12.00 out per 1M tokens, pay as you go.

Which endpoints serve gemini-3.1-pro-preview?

gemini-3.1-pro-preview is served on POST /v1/chat/completions (OpenAI-compatible). Any Router One API key works there.

What is gemini-3.1-pro-preview's context window?

gemini-3.1-pro-preview accepts up to 1.05M tokens of context per request on Router One.

Start using gemini-3.1-pro-preview

Create an API key and call gemini-3.1-pro-preview at $0.20 in / $12.00 out per 1M tokens on Router One — pay as you go, with per-request cost and latency visibility.

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