How to Get Gemini API Key: Step-by-Step Guide

How to Get a Gemini API Key: Quick Answer

1. Open Google AI Studio.
2. Sign in and accept the terms if prompted.
3. Open Dashboard > API Keys.
4. Choose or import a Google Cloud project.
5. Click Create API key and copy the generated key.
6. Store the key as an environment variable before using it in code.

What Is a Gemini API Key?

A Gemini API key is a private credential that allows an application to access Google's Gemini models through the Gemini Developer API. The key connects each request to a Google Cloud project, where Google tracks permissions, usage limits, and billing.

One key can work with different Gemini models available to the project. You do not need separate keys for Gemini 2.5 Flash, Gemini 2.5 Pro, or other supported models. Your code specifies which model to use.

How to Get a Gemini API Key in 7 Steps

1. Open Google AI Studio

Go to the Google AI Studio API Keys page and sign in with your Google Account. Accept Google's terms if this is your first visit.

2. Go to the API Keys Page

Open Dashboard from the left panel and select API Keys. If you are a new user, AI Studio may already display a key connected to a default Google Cloud project. If a key is available, you can copy it and move to Step 5.

3. Choose a Google Cloud Project

Every Google Gemini API key must belong to a Google Cloud project. You can use the default project for testing or choose an existing project for an application that already uses Google Cloud.

If the project is missing, go to Dashboard > Projects > Import projects. Select the project, click Import, and return to the API Keys page. You must have access to the project before you can import it.

4. Create the API Key

Click Create API key and select the project. AI Studio will generate the key and connect it to that project.

New keys created in AI Studio are authorization keys, which Google restricts to the Gemini API by default. If the button is unavailable, ask the project administrator for permission to create API keys and enable services.

5. Copy the Key

Click the copy icon beside the generated key. Do not paste it directly into your source code, a shared document, or a public repository. Treat it like a password.

6. Set the Environment Variable

The Google Gen AI SDK can read the key from GEMINI_API_KEY. On macOS or Linux, add this command to your terminal configuration file:

export GEMINI_API_KEY="YOUR_API_KEY"

Reload the terminal or the configuration file after saving.

On Windows, search and open Environment Variables in System Properties, and click New under User variables. Use GEMINI_API_KEY as the variable name and paste the key as its value. Open a new terminal after saving it.

7. Test the Gemini API Key

Install the Google Gen AI SDK for Python:

pip install -U google-genai

Then run a small request:

from google import genai

client = genai.Client()
response = client.models.generate_content(
    model="gemini-2.5-flash",
    contents="Reply with: The Gemini API key works."
)

print(response.text)

The SDK reads the key from the environment variable. If the script returns a response, the key, project, and selected model are working.

How to Keep a Gemini API Key Secure

• Store the key in an environment variable during local development.
• Use a secret manager when deploying the application.
• Keep .env files out of Git by adding them to .gitignore.
• Never expose a permanent key in browser or mobile application code.
• Replace the key immediately if it appears in a public repository or shared message.

Common Gemini API Key Issues

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Conclusion

Once the test request returns a response, your Gemini API key is ready to use. Keep it outside your source code and replace it immediately if it is ever exposed. The same key can access any supported Gemini model available to the linked Google Cloud project.

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Frequently Asked Questions

1. How do I get a Gemini 2.5 API key for free?

Create a regular Gemini API key in Google AI Studio and select a free-tier eligible Gemini 2.5 model in your request. Gemini 2.5 does not require a separate key.

2. Where can I find an existing Gemini API key?

Open Dashboard > API Keys in Google AI Studio. If the key is missing, import the Google Cloud project connected to it.

3. Can I use a Gemini API key in frontend code?

Do not place a permanent key in browser or mobile code because users can extract it. Send Gemini API requests through a protected backend instead.