Upgrade Node.js to the latest version on Mac OS

Here's how I successfully upgraded from v0.8.18 to v0.10.20 without any other requirements like brew etc, (type these commands in the terminal):

1. sudo npm cache clean -f (force) clear you npm cache
2. sudo npm install -g n install n (this might take a while)
3. sudo n stable upgrade to the current stable version

Note that sudo might prompt your password.

Additional note regarding step 3: stable can be exchanged for latest, lts (long term support) or any specific version number such as 0.10.20.

If the version number doesn't show up when typing node -v, you might have to reboot.

These instructions are found here as well: davidwalsh.name/upgrade-nodejs
More info about the n package found here: npmjs.com/package/n
More info about Node.js' release schedule: github.com/nodejs/Release

Because this seems to be at the top of Google when searching for how to upgrade nodejs on mac I will offer my tip for anyone coming along in the future despite its age.

Upgrading via NPM
You can use the method described by @Mathias above or choose the following simpler method via the terminal.

sudo npm cache clean -f
sudo npm install -g n
sudo n stable

After which you may opt to confirm the upgrade

node -v

Your nodejs should have upgraded to the latest version. If you wish to upgrade to a specific one say v0.8.19 then instead of

sudo n stable

use

sudo n 0.8.19

EDIT Avoid using sudo unless you need to. Refer to comment by Steve in the comments

If you initially installed Node.js with Homebrew, run:

brew update
brew upgrade node
npm install -g npm

Or as a one-liner:

brew update && brew upgrade node && npm install -g npm

---

A convenient way to change versions is to use nvm:

brew install nvm

To install the latest version of Node.js with nvm:

nvm install node

---

If you installed via a package, then download the latest version from nodejs.org. See Installing Node.js and updating npm.