Claude Code Complete Installation Guide
Claude Code is an AI-powered coding assistant CLI tool provided by Anthropic. This comprehensive guide covers installation methods for Windows, Mac, Linux, and all major platforms.
What is Claude Code
Claude Code is an innovative tool that allows you to code while interacting with AI directly from your terminal.
Key Features
- Terminal Integration: Access Claude AI directly from the command line
- Context Awareness: Automatically understands your project files
- MCP Support: Integrates with external tools via Model Context Protocol
- Cross-Platform: Compatible with Windows, Mac, and Linux
System Requirements
- Node.js: v18.0.0 or higher (recommended: v20+)
- OS: Windows 10+, macOS 11+, Linux (major distributions)
- Memory: Minimum 4GB (recommended: 8GB+)
- Storage: 500MB+ free space
macOS Installation
On macOS, using Homebrew is the simplest method.
Method 1: Homebrew (Recommended)
If Homebrew is already installed, run:
brew install claude-code
Verify the installation:
claude --version
Method 2: Via npm
If Node.js is installed, you can use npm:
npm install -g @anthropic-ai/claude-code
Administrator privileges may be required for global installation:
sudo npm install -g @anthropic-ai/claude-code
Initial Setup
After installation, authenticate:
claude login
A browser window will open for Anthropic account authentication. Once completed, you’ll see a confirmation message in the terminal.
Windows Installation
On Windows, you can choose between npm, WSL, or native installation.
Method 1: Via npm (Recommended)
After installing Node.js, run:
npm install -g @anthropic-ai/claude-code
If you encounter execution policy errors in PowerShell:
Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser
Method 2: WSL (Windows Subsystem for Linux)
Using WSL allows you to run Claude Code in a Linux environment.
Install WSL:
wsl --install
After restarting, install Claude Code within WSL:
# For Ubuntu/Debian
curl -fsSL https://deb.nodesource.com/setup_20.x | sudo -E bash -
sudo apt-get install -y nodejs
npm install -g @anthropic-ai/claude-code
Method 3: Git Bash
If using Git Bash, you can install via npm:
npm install -g @anthropic-ai/claude-code
Windows Considerations
- PATH Configuration: Ensure npm global bin directory is in your PATH environment variable
- Firewall: You may be prompted to allow access on first run
- Antivirus: Add to exceptions if falsely detected
Linux Installation
Installation methods for major Linux distributions.
Ubuntu/Debian-based
Set up Node.js:
# Install Node.js 20.x
curl -fsSL https://deb.nodesource.com/setup_20.x | sudo -E bash -
sudo apt-get install -y nodejs
Install Claude Code:
sudo npm install -g @anthropic-ai/claude-code
Fedora/RHEL/CentOS-based
# Install Node.js 20.x
curl -fsSL https://rpm.nodesource.com/setup_20.x | sudo bash -
sudo dnf install -y nodejs
# Install Claude Code
sudo npm install -g @anthropic-ai/claude-code
Arch Linux
# Using yay
yay -S nodejs npm
npm install -g @anthropic-ai/claude-code
Avoiding Permission Errors
If you encounter permission errors during global installation, change npm’s global directory:
mkdir ~/.npm-global
npm config set prefix '~/.npm-global'
echo 'export PATH=~/.npm-global/bin:$PATH' >> ~/.bashrc
source ~/.bashrc
Then install without sudo:
npm install -g @anthropic-ai/claude-code
Detailed npm Installation
Using npm is a universal method across all platforms.
Global Installation
npm install -g @anthropic-ai/claude-code
Local Installation (Per Project)
For use in specific projects only:
cd your-project
npm install @anthropic-ai/claude-code
npx claude
Version-Specific Installation
To install a specific version:
npm install -g @anthropic-ai/claude-code@1.0.89
Updating
To update an existing installation to the latest version:
npm update -g @anthropic-ai/claude-code
Or:
npm install -g @anthropic-ai/claude-code@latest
Initial Setup and Authentication
After installation, perform the initial setup.
Login
claude login
A browser will automatically open, prompting you to authenticate with your Anthropic account.
Proxy Configuration
If using a proxy in corporate networks:
export HTTPS_PROXY=http://proxy.example.com:8080
claude login
For Windows PowerShell:
$env:HTTPS_PROXY="http://proxy.example.com:8080"
claude login
Manual API Key Setup
If login doesn’t work, you can manually set the API key:
export ANTHROPIC_API_KEY=your_api_key_here
Get your API key from the Anthropic Console.
Verifying Installation
Confirm that Claude Code is correctly installed.
Check Version
claude --version
The latest version should be displayed.
Display Help
claude --help
This shows a list of available commands.
Test Run
Try Claude Code with a simple command:
claude
When the prompt appears, type:
Hello, Claude! Please tell me about yourself.
If you receive a response from Claude AI, the setup is complete.
Troubleshooting
Common issues and their solutions.
Command Not Found
Symptom: claude: command not found
Causes:
- npm global bin directory not in PATH
- Installation didn’t complete properly
Solutions:
# Check npm global bin path
npm config get prefix
# Add to PATH (for bash)
echo 'export PATH="$(npm config get prefix)/bin:$PATH"' >> ~/.bashrc
source ~/.bashrc
# For zsh
echo 'export PATH="$(npm config get prefix)/bin:$PATH"' >> ~/.zshrc
source ~/.zshrc
Outdated Node.js Version
Symptom: Error: Node.js version 18.0.0 or higher is required
Solution:
Update Node.js:
# macOS (Homebrew)
brew upgrade node
# Ubuntu/Debian
curl -fsSL https://deb.nodesource.com/setup_20.x | sudo -E bash -
sudo apt-get install -y nodejs
# Windows
# Download the latest version from the official Node.js website
npm Permission Errors
Symptom: EACCES: permission denied
Solution:
Change npm’s global directory:
mkdir ~/.npm-global
npm config set prefix '~/.npm-global'
echo 'export PATH=~/.npm-global/bin:$PATH' >> ~/.bashrc
source ~/.bashrc
Reinstall (without sudo):
npm install -g @anthropic-ai/claude-code
Character Encoding Issues in WSL
Symptom: Japanese characters not displaying correctly
Solution:
Set locale:
sudo apt-get install language-pack-ja
sudo update-locale LANG=ja_JP.UTF-8
Change terminal font to one that supports Japanese characters.
Authentication Errors
Symptom: Authentication failed
Solutions:
- Logout and login again:
claude logout
claude login
- Manually set API key:
export ANTHROPIC_API_KEY=your_api_key
- Check proxy settings (if in proxy environment)
Update Not Reflecting
Symptom: Old version shown with claude --version
Solution:
Clear cache and reinstall:
npm cache clean --force
npm uninstall -g @anthropic-ai/claude-code
npm install -g @anthropic-ai/claude-code
Uninstallation
How to uninstall Claude Code when no longer needed.
If Installed via npm
npm uninstall -g @anthropic-ai/claude-code
If Installed via Homebrew (macOS)
brew uninstall claude-code
Removing Configuration Files
To also remove authentication and configuration files:
# macOS/Linux
rm -rf ~/.config/claude-code
rm -rf ~/.claude
# Windows
rmdir /s "%APPDATA%\claude-code"
Summary
The recommended installation methods for Claude Code by platform:
- macOS: Homebrew (
brew install claude-code) - Windows: npm or WSL
- Linux: Global installation via npm
After installation, complete authentication with claude login and start using immediately. If you encounter issues, refer to the troubleshooting section in this guide.
Leverage Claude Code to build an efficient development environment!