GooglePaidOperational

Gemini 3.1 Pro Preview

API model name: gemini-3.1-pro-preview

Gemini 3.1 Pro Preview is Google's chat model, served on the Api.Airforce unified API. It has a 2M-token context window. Beyond text, it accepts image, audio, video, document as input. Capabilities include Vision, Tool calling, Reasoning, Documents, Prompt caching. It is priced at $2.60 per million input tokens and $15.60 per million output tokens. Knowledge cutoff: 2026-03. Access it through the OpenAI-compatible API with one key, alongside 100+ other models on Api.Airforce.

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Pricing

Input / 1M tokens
$2.60
Output / 1M tokens
$15.60
Cache read / 1M tokens
$0.26

Pricing by input length

Input lengthInput / 1M tokensOutput / 1M tokens
≤200000$2.60$15.60
long_context$5.20$23.40

Specifications

Provider
Google
Type
chat model
Context window
2M tokens
Max output
66K tokens
Knowledge cutoff
2026-03
Input
text, image, audio, video, document
Output
text
Prompt caching
Supported

Capabilities

VisionTool callingReasoningDocumentsPrompt cachingStreaming

What is Gemini 3.1 Pro Preview used for?

  • Chatbots & assistants — conversational AI, drafting, summarizing and Q&A.
  • Image understanding — analyze photos, screenshots, charts and scanned documents.
  • Agents & automation — function calling and tool use for multi-step workflows.
  • Complex reasoning — math, coding and step-by-step problem solving.
  • Document analysis — summarize and answer questions across long files.
  • Long-context tasks — process entire documents or codebases in a single prompt.
  • Real-time experiences — stream tokens for responsive chat and apps.

Gemini 3.1 Pro Preview vs. similar models

ModelIntelligenceContextInput / 1MOutput / 1M
Gemini 3.1 Pro Preview—2M$2.60$15.60
[SP]gemini 2.5 Pro——$3.97$0.02
[SP]gemini 3.1 Pro Preview——$3.97$0.02
[SP]gemini 3.5 Flash——$13.27$0.02

Prices are Api.Airforce pay-as-you-go rates per 1M tokens. Context is the maximum input length.

Related models

[SP]gemini 2.5 ProGoogle · $3.97 / 1M[SP]gemini 3.1 Pro PreviewGoogle · $3.97 / 1M[SP]gemini 3.5 FlashGoogle · $13.27 / 1M[SP]gemini 3.6 FlashGoogle · $3.97 / 1MGemini 2.0 FlashGoogle · $0.13 / 1MGemini 2.0 Flash 001Google · $0.13 / 1MGemini 2.0 Flash LiteGoogle · $0.09 / 1MGemini 2.0 Flash Lite 001Google · $57.41 / 1MGemini 2.5 Computer Use Preview 10Google · $57.41 / 1MGemini 2.5 FlashGoogle · $0.53 / 1MGemini 2.5 Flash Image PreviewGoogle · $0.07 / 1MGemini 2.5 Flash Image TokenGoogle · $0.33 / 1M

Gemini 3.1 Pro Preview — frequently asked questions

How much does Gemini 3.1 Pro Preview cost?
Gemini 3.1 Pro Preview is billed pay-as-you-go at $2.60 per 1M input tokens and $15.60 per 1M output tokens. There is no subscription — you only pay for what you use.
What is the context window of Gemini 3.1 Pro Preview?
Gemini 3.1 Pro Preview supports a context window of up to 2M tokens. It can return up to 66K tokens in a single response.
What can Gemini 3.1 Pro Preview do?
Gemini 3.1 Pro Preview supports Vision, Tool calling, Reasoning, Documents, Prompt caching.
Is Gemini 3.1 Pro Preview free to use?
Gemini 3.1 Pro Preview is a paid, pay-as-you-go model — no subscription, you are only charged for usage.
How do I use Gemini 3.1 Pro Preview via the API?
Gemini 3.1 Pro Preview is OpenAI-compatible. Point any OpenAI SDK at https://api.airforce/v1 and pass the model ID gemini-3.1-pro-preview with your Api.Airforce API key.
Who makes Gemini 3.1 Pro Preview?
Gemini 3.1 Pro Preview is Google's chat model, served through the unified Api.Airforce gateway alongside 100+ other models.
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