Gemini API Key — How to Obtain and Use It with the OpenAI SDK

A Gemini API key is the credential that authenticates your calls to Google's Gemini models: each request carries the key in a Authorization header, and usage is measured and billed per token. There are two ways to get a working key: Google AI Studio (official), which provides a key for Gemini only, or Kunavo, where one OpenAI-compatible key reaches Gemini, Claude, GPT, and image, video, and audio models — without needing a Google Cloud project. This guide shows how to get a key using either option and how to make your first call.

Option 1 — Google AI Studio (official)

This is the right path if Gemini is the only model you'll call.

1. Sign in to aistudio.google.com with a Google account.
2. Open Get API key → Create API key. Keys have the format AIza....
3. The free tier is limited and intended for prototypes. For production volume, you must attach the key to a Google Cloud project with a billing account enabled.

If you also use Claude, image, or video models, this option leaves you managing a separate key, SDK, and bill for each provider.

Option 2 — Kunavo (recommended for production)

Kunavo puts Gemini behind an OpenAI-compatible API. One sk-kn- key calls Gemini and all other models, with a single Stripe-billed wallet and no Google Cloud project required. Gemini costs around 70% below Google's list price — for example, Flash costs $0.09 per 1M input tokens and $0.75 per 1M output tokens. It's pay-as-you-go with a $10 minimum deposit, and your balance never expires.

1. Sign up at kunavo.com.
2. Add $10 — pay as you go, and your balance never expires.
3. Create a key at /app/keys. It starts with sk-kn- and is shown only once; save it in an environment variable.
4. Make a call by pointing the OpenAI SDK to https://api.kunavo.com/v1 and using a Gemini slug.

Quickstart

Keep the official OpenAI SDK. Change base_url and the model name — nothing else:

import os
from openai import OpenAI

client = OpenAI(
    api_key=os.environ["KUNAVO_API_KEY"],
    base_url="https://api.kunavo.com/v1",  # a única linha que muda
)

resp = client.chat.completions.create(
    model="gemini-2-5-flash",
    messages=[{"role": "user", "content": "Explique RAG em duas frases."}],
)
print(resp.choices[0].message.content)

Key security

• Never expose the key on the client. Browser and mobile bundles are public — always proxy through your own server. Store the key in environment variables, outside version-controlled code.
• Use one key per project or environment, so a leak can be revoked without disrupting anything else.
• Rotate keys regularly. Kunavo allows multiple active keys at once, so rotation is a clean overlap rather than a hard cutover.
• Set spending limits per key in the dashboard and monitor /app/usage to spot unexpected traffic broken down by key.

Frequently asked questions