GoogleText / ChatGemini 3.1 Pro Preview API: Google's multimodal flagship
Gemini 3.1 Pro Preview via the ApexApi gateway
Gemini 3.1 Pro is Google's flagship multimodal model — built for deep native understanding across text, images, and long context, with strong reasoning and grounding. Available through ApexApi's unified, OpenAI-compatible API.
Gemini 3.1 Pro Preview is served through ApexApi's unified, OpenAI-compatible API — one key, one format, with smart routing and automatic failover. Provider: Google AI.
Why Gemini 3.1 Pro Preview
Native multimodality
Reasons across text and images with strong cross-modal grounding.
Very long context
Handles large inputs for document, codebase, and multi-file analysis.
Strong reasoning
Capable general reasoning for analysis, planning, and code.
Specifications
- Modality
- chat
- Context window
- 1048.6K tokens
- Max output
- 65.5K tokens
- Streaming
- Yes
- Tool / function calling
- Yes
- Vision input
- Yes
Gemini 3.1 Pro Preview pricing
Pay-per-use — no subscription, no minimums. Buy credits and pay only for what you call. Transparent, per-call pricing across every model.
Getting started with Gemini 3.1 Pro Preview
OpenAI-compatible — point your client at ApexApi, swap your key, and call it. No new SDK to learn.
from openai import OpenAI
client = OpenAI(
base_url="https://api.apexapi.dev/v1",
api_key="<YOUR_APEXAPI_KEY>",
)
response = client.chat.completions.create(
model="google/gemini-3.1-pro-preview",
messages=[{"role": "user", "content": "Hello!"}],
)
print(response.choices[0].message.content)Gemini 3.1 Pro Preview use cases
What teams build with Gemini 3.1 Pro Preview on ApexApi.
Document AI
Understand long, mixed-content documents end to end.
Multimodal apps
Vision + text understanding for richer assistants.
Analysis & planning
Complex reasoning over large context windows.
Gemini 3.1 Pro Preview vs other models
How it compares — and on ApexApi you can switch between any of them with a single string change, same key, same endpoint.
Gemini 3.1 Pro Preview vs GPT-5.5
GPT-5.5 emphasizes instruction fidelity and tool orchestration; Gemini 3.1 Pro leans into native multimodality and very long context.
Learn more about GPT-5.5 API →Gemini 3.1 Pro Preview vs Claude Opus 4.7
Opus 4.7 is the long-form text/coding specialist; Gemini 3.1 Pro is the multimodal long-context option.
Learn more about Claude Opus 4.7 API →Why build on ApexApi
One API, every model
OpenAI-compatible — swap the base URL and key, keep your code. Call 14+ providers and hundreds of models through a single integration.
Smart routing & failover
Per-model provider chains with automatic failover. If one provider degrades, requests route to the next — your app stays up.
Pay-per-use, no lock-in
Buy credits, pay only for what you call. No subscriptions, no minimums. Switch models anytime with a single string change.
Gemini 3.1 Pro Preview API — FAQ
How do I use the Gemini 3.1 Pro API?
Create an ApexApi key, then point your client at https://api.apexapi.dev/v1 and use the model slug. Send a request to /v1/chat/completions with the model slug — the API is OpenAI-compatible, so most OpenAI SDKs work by changing the base URL and key.
Is the Gemini 3.1 Pro API OpenAI-compatible?
Yes. ApexApi exposes Gemini 3.1 Pro through the same OpenAI-compatible interface used across the whole catalog — swap the base URL and API key and keep your existing code.
How much does Gemini 3.1 Pro cost on ApexApi?
Pay-per-use — see the live price in the Pricing section above. There's no subscription or minimum; you buy credits and pay only for what you call.
Can I switch from Gemini 3.1 Pro to another model later?
Yes — change a single string (the model slug) to call any other model in the catalog through the same endpoint and key. No re-integration.
Ready to build with Gemini 3.1 Pro Preview?
One API key. Every major AI model. Pay only for what you use.
Get your API key — free to start