Background Introduction

Google's Gemini API provides developers with specific free quotas, allowing the integration of Gemini models into their own applications. Model accessibility: Developers can call the Gemini 2.5 Pro model and its lightweight version, Gemini 2.5 Flash, for free.

Standard Free Quota: By obtaining an API key from Google AI Studio, each developer can receive a generous free usage quota. This includes 300,000 tokens per day (including prompts and responses) and a rate limit of 60 requests per minute.

I. Free Application for Gemini API Key

Open https://aistudio.google.com/app/apikey in your browser to create an API key.

This step requires both network and region to be met. Subsequent usage will not require meeting network conditions.

With the Gemini API key, you can call the API to use the capabilities of the Gemini large model.

The Gemini API cannot be directly used in the domestic internet environment, so this article introduces a method to use Gemini without a proxy.

II. Using openai-gemini

1. Find openai-gemini on GitHub

openai-gemini is a serverless proxy project used to convert the Gemini API into the OpenAI API.

Project address: https://github.com/PublicAffairs/openai-gemini

The Gemini API is free, but many tools are specifically designed to work with the OpenAI API. This project can convert the Gemini API into the OpenAI API and call it via serverless. We can find a free serverless service accessible in China for intermediate transfer to meet domestic calling usage needs.

Here, we introduce deploying openai-gemini to Vercel.

Vercel is a leading web development platform that provides a one-stop solution for building, deploying, and managing modern high-performance websites and web applications.

Open https://github.com/PublicAffairs/openai-gemini in your browser, scroll down to find "Deploy with Vercel," and click "Deploy."

After deployment, if you open the newly deployed site in your browser, you will only see a "404 Not Found" message. This is expected, as the API is not designed for direct browser access. It is recommended to bind your own domain name to avoid DNS pollution. At this point, you will have your own Gemini domestic proxy and a website that converts to OpenAI format.