Google: Gemini 3.1 Flash-Lite · fastrouter

Gemini 3.1 Flash-Lite is Google's most cost-efficient Gemini 3-series model, a low-latency multimodal model optimized for high-volume, cost-sensitive workloads such as classification, translation, data extraction, model routing, and simple agentic tasks. It supports a 1,048,576-token context window across text, images, video, audio, and PDFs, with improved instruction following and audio input quality over Gemini 2.5 Flash-Lite, and four configurable thinking levels (minimal, low, medium, high). It supports function calling, structured outputs, code execution, file search, URL context, Google Search and Maps grounding, and context caching. Knowledge cutoff is January 2025.

Base model All models on this base All models of the provider to the provider

Input, $/1M $0.25

Output, $/1M $1.50

Cache read $0.025

Cache write —

Context 1 048 576

Max output 65 536

Accepts audio, files, images, text, video

Last checked 04.11.2026 12:00:14 UTC

Source provider's page

Price alerts

API

OpenAI-compatible API: the official OpenAI SDKs work with this base URL. Replace YOUR_API_KEY with your key from the provider.

API base URL	`https://go.fastrouter.ai/api/v1`
Endpoint	`https://go.fastrouter.ai/api/v1/chat/completions`
Model id	`google/gemini-3.1-flash-lite`

curl

curl https://go.fastrouter.ai/api/v1/chat/completions \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model": "google/gemini-3.1-flash-lite", "messages": [{"role": "user", "content": "Hello!"}], "max_tokens": 256}'

Python

import requests

r = requests.post(
    "https://go.fastrouter.ai/api/v1/chat/completions",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
    json={
      "model": "google/gemini-3.1-flash-lite",
      "messages": [
        {
          "role": "user",
          "content": "Hello!"
        }
      ],
      "max_tokens": 256
    },
)
print(r.json())

JavaScript

const r = await fetch("https://go.fastrouter.ai/api/v1/chat/completions", {
  method: "POST",
  headers: {Authorization: "Bearer YOUR_API_KEY", "Content-Type": "application/json"},
  body: JSON.stringify({
    "model": "google/gemini-3.1-flash-lite",
    "messages": [
      {
        "role": "user",
        "content": "Hello!"
      }
    ],
    "max_tokens": 256
  }),
});
console.log(await r.json());

Request (JSON)

{
  "model": "google/gemini-3.1-flash-lite",
  "messages": [
    {
      "role": "user",
      "content": "Hello!"
    }
  ],
  "max_tokens": 256
}

Response (JSON)

{
  "id": "chatcmpl-...",
  "object": "chat.completion",
  "model": "google/gemini-3.1-flash-lite",
  "choices": [
    {
      "index": 0,
      "message": {
        "role": "assistant",
        "content": "Hi! How can I help?"
      },
      "finish_reason": "stop"
    }
  ],
  "usage": {
    "prompt_tokens": 9,
    "completion_tokens": 12,
    "total_tokens": 21
  }
}

The address is taken from the provider's model list; check it against the provider's documentation.

Provider's API documentation

Source: AI Rate Card, https://airatecard.com/en/c/offer%3Afastrouter%7Cgoogle/gemini-3.1-flash-lite, prices checked 2026-11-04; seller's page: https://fastrouter.ai

Technical details

ID: offer:fastrouter|google/gemini-3.1-flash-lite