Step 1: Install Gemini CLI

Gemini CLI is a free, open-source AI coding agent from Google. It runs in your terminal and can read your project files, write code, and execute commands on your behalf.

Quota: The free tier gives you 60 model requests per minute and 1,000 requests per day — more than enough for building a prototype. See Gemini CLI quota docs for current limits.

Install Node.js first

Gemini CLI requires Node.js 18 or later. Check your version:

# macOS / Linux
node --version

# Windows PowerShell
node --version

If node is not found or the version is below 18, download and install Node.js from https://nodejs.org (choose the LTS version).

Install Gemini CLI

# macOS / Linux
npm install -g @google/gemini-cli

# Windows PowerShell
npm install -g @google/gemini-cli

Verify the installation

# macOS / Linux
gemini --version

# Windows PowerShell
gemini --version

Expected output: a version string such as 0.x.x.

Sign in with your Google account

Launch gemini for the first time:

# macOS / Linux
gemini

# Windows PowerShell
gemini

The CLI opens a browser tab — sign in with any personal Google account. No paid plan required. Once you are signed in, the terminal shows the interactive prompt. Type /quit to exit and return to your shell.