How to install Claude Code (Windows, Mac, Linux)

To install Claude Code, use the official installer for your operating system, reopen your terminal, and check that the command runs. Then start Claude Code inside a project folder and complete sign-in. This guide covers the command-line installation on Windows, Mac, and Linux, followed by a small first-session exercise.

Claude Code can read project files, make changes, and run development commands. Installing it is only the first step: a useful setup also needs the correct project folder and clear instructions. If you are still choosing a tool, read my Claude Code vs Cursor comparison.

Before you start

Use a supported system: macOS 13 or newer, Windows 10 version 1809 or newer, or a supported Linux distribution such as Ubuntu 20.04+ or Debian 10+. Anthropic specifies at least 4 GB of RAM and an internet connection. Check the current system requirements for your exact configuration.

Keep three things separate: the installation, your account access, and your project's dependencies. Installing the coding tool does not install everything needed to run a WordPress, Shopify, or Astro project. Follow that project's own README for its runtime and build setup.

Use a practice repository for your first session. It is easier to learn the workflow on a small project than while trying to solve an urgent client issue.

Install Claude Code on Windows

1. Open PowerShell

Search for PowerShell from the Start menu and open it. Use the PowerShell command below, not the Mac/Linux command. Anthropic documents native Windows installation without requiring an Administrator session.

2. Run the official installer

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

This retrieves and executes Anthropic's installation script. Use the official address, and follow your organisation's software-installation policy on a managed computer. The command is documented in the Claude Code installation overview.

3. Reopen PowerShell and check the version

claude --version

A version response confirms that your terminal can locate the installed program. It does not yet confirm that your account can use it or that a particular project is configured correctly.

Windows or WSL?

Choose native Windows for projects using Windows tools. If your project already runs in WSL, install and run Claude Code inside that Linux environment instead. Avoid mixing terminals during the walkthrough: the project path and available commands can differ between Windows and WSL.

Git for Windows is optional for the current native setup; it provides Git Bash. See the Windows setup details for shell support and WSL differences.

Install Claude Code on Mac

1. Open Terminal

Open Terminal using Spotlight or your Applications folder. Check that you are following the Mac instructions rather than copying a PowerShell command from another guide.

2. Run the native installer

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

Anthropic lists the native installer as its recommended route. Once it finishes, open a new terminal and run the version check:

claude --version

Alternative: use Homebrew

If you already manage development tools through Homebrew, the official alternative is:

brew install --cask claude-code

Choose one installation method and record it. That makes future updates and troubleshooting clearer. The official overview documents both routes.

Install Claude Code on Linux

1. Open your Linux terminal

Use a supported distribution and confirm that curl and Bash are available. Minimal containers and distributions may not include the same utilities as a desktop installation.

2. Run the installer

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

Open a fresh shell after installation, then check:

claude --version

For Alpine and other musl-based environments, follow Anthropic's distribution-specific setup instructions. They require additional packages; do not assume the basic desktop procedure is sufficient.

Sign in and open your first project

Installation and authentication are separate. Claude Code requires eligible account access, such as a supported Claude subscription or a Console account; the free Claude plan does not include it. Organisations may also use supported cloud providers. Confirm the appropriate route in the authentication documentation.

Open a terminal in your project folder. For example, replace the path below with your actual folder, then start the tool:

cd path/to/your-project
claude

Follow the browser sign-in flow when prompted. Review any account or organisation selection carefully, particularly if you have both personal and work accounts. The official quickstart walks through the initial session.

For your first request, ask for an explanation rather than a change:

Explain the structure of this project and how to run it locally. Do not edit any files yet.

Compare the response with the repository's README. This gives you a chance to notice the wrong working directory, missing context, or misunderstood conventions before asking for implementation work.

Verify the setup before client work

A version number proves that the executable starts. A successful sign-in proves account access. Neither proves that your application builds or that the agent's next change will be correct.

Run the project's documented checks yourself first. Note any existing failures so they do not get confused with problems introduced later. For a website, open the local preview and inspect the main user flow as well as the terminal output.

Then request one small change on a branch. Specify the desired result, the files or sections that should remain unchanged, and how you will verify the outcome. Review the diff before committing. Treat publishing or deploying as a separate action from preparing the code.

For installation diagnostics, run:

claude doctor

Anthropic documents this command as an installation and settings check in its setup guide.

Common installation problems

The terminal cannot find claude

Reopen your terminal first. If the problem remains, check whether installation completed and whether the executable's directory is on PATH. The native location is normally ~/.local/bin on Mac/Linux and %USERPROFILE%\.local\bin on Windows. Follow the platform-specific PATH troubleshooting steps.

Avoid repeatedly installing through different methods without checking the existing installation. Multiple copies can make it unclear which executable your terminal is launching.

A Windows command fails immediately

Confirm which shell you opened. The PowerShell installer uses irm; the Mac/Linux installer uses curl and Bash. An error about irm being unrecognised often means the PowerShell command was pasted into Command Prompt. See Windows command troubleshooting.

Installation succeeds but login fails

Read the actual error before reinstalling. Account access, organisation permissions, network restrictions, and expired authentication can require different fixes. Use Anthropic's installation and login troubleshooting guide to match the symptom.

If you ask someone for help, share the operating system, installation method, and error text. Remove credentials and personal account information from screenshots or logs.

Keep your installation maintained

Native installs update automatically by default. Homebrew installations require an explicit upgrade:

brew upgrade claude-code

Use the updater that matches your installation method. Anthropic's update instructions explain release channels and other package-manager options.

Ready for your first useful task

Once you install Claude Code, sign in, and verify your project, start with a small task you can review completely. Good instructions and a clear acceptance check will help more than asking the tool to rebuild everything at once.

If you need help configuring a team workflow or improving an existing AI-built application, explore my Claude Code development and consulting service or contact me with your project details.