Claude Code Installation

Problem: You want to install Claude Code but are not sure where to start. Here is the shortest path from zero to a working AI terminal.

How to Install Claude Code: Quick Start

Anthropic now ships native installers as the recommended method. No Node.js needed:

Windows PowerShell (Recommended):

irm https://claude.ai/install.ps1 | iex

macOS / Linux:

curl -fsSL https://claude.ai/install.sh | bash

Homebrew (macOS/Linux):

brew install --cask claude-code

Run claude --version to confirm. Success looks like: a version number prints without errors.

Step-by-Step: Install Claude Code on Any Platform

Before you install Claude Code, check that you have:

1. Terminal access (Command Prompt, PowerShell, or Bash)
2. An Anthropic API key from console.anthropic.com
3. Node.js 18+ (only if you plan to install via npm)

Install Claude Code on Windows

Windows supports a few install paths. Pick the one that fits your workflow:

Option 1: Native Windows (Recommended)

# PowerShell (Run as Administrator)
irm https://claude.ai/install.ps1 | iex
claude --version

Option 2: Git Bash

Install Git for Windows, then:

curl -fsSL https://claude.ai/install.sh | bash
claude --version

Option 3: WSL (Ubuntu)

# Install WSL if needed (PowerShell as Administrator)
wsl --install -d Ubuntu
 
# Inside Ubuntu terminal
curl -fsSL https://claude.ai/install.sh | bash
claude --version

Windows users: the native installer no longer needs Node.js. On WSL, run Claude Code from your Linux terminal.

Install Claude Code on macOS

Option 1: Homebrew (Recommended)

brew install --cask claude-code
claude --version

Option 2: Native Installer

curl -fsSL https://claude.ai/install.sh | bash
claude --version

Option 3: npm (if you prefer Node.js)

npm install -g @anthropic-ai/claude-code
 
# If you see "command not found", fix PATH:
echo 'export PATH="$(npm config get prefix)/bin:$PATH"' >> ~/.zshrc
source ~/.zshrc
claude --version

Install Claude Code on Linux

Option 1: Native Installer (Recommended)

curl -fsSL https://claude.ai/install.sh | bash
claude --version

Option 2: Homebrew

brew install --cask claude-code
claude --version

Option 3: npm (requires Node.js 18+)

# Create user npm directory (prevents sudo requirements)
mkdir ~/.npm-global
npm config set prefix '~/.npm-global'
echo 'export PATH=~/.npm-global/bin:$PATH' >> ~/.bashrc
source ~/.bashrc
 
# Install Claude Code
npm install -g @anthropic-ai/claude-code
claude --version

Configure Your API Key

Once the install succeeds, set up authentication:

claude
# Paste your API key when prompted

Get your API key: open console.anthropic.com, create an account, go to API Keys, and generate a new key starting with sk-.

Verify Your Installation

Test your Claude Code setup:

claude --version    # Shows version number
claude doctor       # Runs diagnostics

Quick functionality test:

mkdir test-project && cd test-project
echo "console.log('Hello!');" > test.js
claude

In the Claude prompt: "Read test.js and explain it"

Success: Claude reads the file and explains the JavaScript.

Common Errors When You Install Claude Code

Error: "Command Not Found"

Cause: PATH configuration is missing after install

Fix:

which claude    # Check if installed
npm list -g @anthropic-ai/claude-code
 
# Add to PATH manually
echo 'export PATH="$PATH:/usr/local/lib/node_modules/@anthropic-ai/claude-code/bin"' >> ~/.bashrc
source ~/.bashrc

Error: "EBADPLATFORM"

Cause: npm install ran on an unsupported platform config

Fix: use the native installer instead of npm:

# Windows PowerShell
irm https://claude.ai/install.ps1 | iex

Error: "EACCES Permission Denied"

Cause: npm wants sudo (not a safe habit)

Fix: set up a user-level npm directory (see the Linux section above). This works on every platform.

Nuclear Reset (Fixes 95% of Issues)

When nothing else works, reset the whole thing:

npm uninstall -g @anthropic-ai/claude-code
rm -rf ~/.claude ~/.npm/_cacache
npm cache clean --force
npm install -g @anthropic-ai/claude-code
claude --version

What to Do After You Install Claude Code

Once claude --version comes back clean:

1. Build your first project: First Project Guide
2. Learn the interface: What is Claude Code
3. Configure settings: Configuration Basics
4. Fix common problems: Troubleshooting Guide
5. See real examples: Examples & Templates

Pro tip: run claude doctor any time something feels broken. It auto-detects most config issues and suggests fixes.