Making Python 3 the Default on macOS

AUGUST 13, 2020

While macOS ships with Python 2 by default, you can install set Python 3 as the default Python version on your Mac.

First, you install Python 3 with Homebrew.

brew update && brew install python

To make this new version your default add the following line to your ~/.zshrc file.

alias python=/usr/local/bin/python3

Then open a new Terminal and Python 3 should be running.

Let's verify this is true.

python --version # e.g. Python 3.8.5

How do I find the python3 path?

Homebrew provides info about any installed "bottle" via the info command.

brew info python
# python@3.8: stable 3.8.5 (bottled)
# Interpreted, interactive, object-oriented programming language
# /usr/local/Cellar/python@3.8/3.8.5 (4,372 files, 67.7MB) *
# ...

And you can find the path we're looking for grep.

brew info python | grep bin
# /usr/local/bin/python3
# /usr/local/opt/python@3.8/libexec/bin

How do I use Python 2 if I need it?

Your system's Python 2.7 is still there.

/usr/bin/python --version # e.g Python 2.7.16

You can also use Homebrew's Python 2.

brew install python@2

Before you go

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