This guide shows you three ways to change which Claude model you're using with Claude Code: the quick /model command for instant changes, the --model flag for one-time session changes, and environment variables to set your preferred model as the permanent default.

Easiest method: Use /model command

The simplest way to change models is to use the /model command directly within Claude Code. This works immediately without restarting your terminal.

Supported models

Change model for current session only

Use the --model flag when starting Claude Code.

Change default model for all future sessions

Step 1) Check your shell type by running: echo $SHELL

Step 2) Add model setting to your shell config:

For ZSH users (macOS)

For BASH users (Linux)

Step 3) Apply the changes:

Step 4) Close Terminal completely, then reopen it.

Step 5) Start Claude Code in a fresh Terminal session: claude.

Now your chosen model will be the default for all future Claude Code sessions.