Install nodejs v20 on Debian and Ubuntu based distributions

step 1 : Download and import the Nodesource GPG key

sudo apt-get update
sudo apt-get install -y ca-certificates curl gnupg
sudo mkdir -p /etc/apt/keyrings
curl -fsSL https://deb.nodesource.com/gpgkey/nodesource-repo.gpg.key | sudo gpg --dearmor -o /etc/apt/keyrings/nodesource.gpg

step 2 : Create deb repository

NODE_MAJOR=20
echo "deb [signed-by=/etc/apt/keyrings/nodesource.gpg] https://deb.nodesource.com/node_$NODE_MAJOR.x nodistro main" | sudo tee /etc/apt/sources.list.d/nodesource.list

optional: here we are installing nodejs v20 but if you want to install v18 change NODE_MAJOR=18 in above command. Similarly if you want to install nodejs v16 then change NODE_MAJOR=16.

step 3 : Run Update and Install

sudo apt-get update
sudo apt-get install nodejs -y

congratulations you just installed nodejs

To uninstall nodejs

sudo apt-get purge nodejs &&\
rm -r /etc/apt/sources.list.d/nodesource.list &&\
rm -r /etc/apt/keyrings/nodesource.gpg

NodeSource provides binary distributions of Node.js; complete installation instructions can be found here. The instructions have been copied below for your reference. Instructions are the same for updating to the latest version.

Run once:

sudo apt-get update
sudo apt-get install -y ca-certificates curl gnupg
sudo mkdir -p /etc/apt/keyrings
curl -fsSL https://deb.nodesource.com/gpgkey/nodesource-repo.gpg.key | sudo gpg --dearmor -o /etc/apt/keyrings/nodesource.gpg

Run whenever you want to change the major version of Node.js:

NODE_MAJOR=20
echo "deb [signed-by=/etc/apt/keyrings/nodesource.gpg] https://deb.nodesource.com/node_$NODE_MAJOR.x nodistro main" | sudo tee /etc/apt/sources.list.d/nodesource.list
sudo apt-get update
sudo apt-get install nodejs -y

Prior to August 2023: Previously versions of this answer involved the use of a series of setup_XX.x scripts that you'd run to install/update Node.js:

curl -fsSL https://deb.nodesource.com/setup_current.x | sudo -E bash -
sudo apt-get install -y nodejs

But as @eis pointed out, these scripts are no longer supported. To see the previous answers, please look at the edit history for this answer.

I found a simple solution that doesn't involve recompiling the full Node.js binaries which can take a very long time, especially on embedded systems, by compiling the right version of glibc instead and using patchelf to patch the original binary to work with it.

Detailed instructions can be found here:

https://stackoverflow.com/a/77247394/1163708

All Platforms (Mac, Linux & Windows) 2024

If you just need to upgrade your old version of Node.js to the latest one and don't need multiple versions, simply over-write your existing executable with the new one.

Download the Latest Node.js from nodejs.org/en/download

This Just Works! ^TM on all platforms and is the easiest/fastest method.
When you run node -v in your terminal you will see the the latest version.

Mac

If you originally installed Node.js using brew then run:

brew upgrade node

Managing Multiple Versions of Node.js:

If you need to run multiple versions of Node.js on your machine e.g. if you have an older project that targets a specific version on AWS Lambda, then NVM (Node Version Manger) is your friend!

Step 1 - Get NVM

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.3/install.sh | bash

If you're curious about the installation command read the source code
... its been reviewed by several node.js security experts

Step 2 - Install the Specific Version of Node.js you need

Once you've got NVM you can install a specific version of Node.js using the nvm command:

nvm install v22.16.0

Note: you may need to close & re-open your terminal window for nvm command to be available.

You should expect to see something like this in your terminal:

Now using node v22.16.0

You now have the latest Node.js on your machine.
And if you need to temporarily switch to a different/previous version, you can do it with a simple nvm command.

Note: avoid using sudo with Node/NPM as it violates the security principal of least privilege

NVM is considered "better" than N for managing multiple Node.js versions because the verbose commands mean it is much easier to keep track of what you are doing in your Terminal/SSH Log. It is used by the team at NPM the creators/custodians of the Node.js World!