Difference between npx and npm?


Difference between npx and npm?

I have just started Learning React and facebook helps in simplifying the initial setup by providing the following ready-made project.
Link to Facebook account on Github: https://github.com/facebook/create-react-app
If I have to install the skeleton project I have to type npx create-react-app my-app in command-line.
I was wondering why does the facebook account in Github have npx create-react-app my-app rather than npm create-react-app my-app?


Solution 1:

Introducing npx: an npm package runner

NPMManages packages but doesn’t make life easy executing any.
NPX – A tool for executing Node packages.

NPX comes bundled with NPM version 5.2+

NPM by itself does not simply run any package. it doesn’t run any package in a matter of fact. If you want to run a package using NPM, you must specify that package in your package.json file.

When executables are installed via NPM packages, NPM links to them:

  1. local installs have “links” created at ./node_modules/.bin/ directory.
  2. global installs have “links” created from the global bin/ directory (e.g. /usr/local/bin) on Linux or at %AppData%/npm on Windows.

Documentation you should read


One might install a package locally on a certain project:

npm install some-package

Now let’s say you want NodeJS to execute that package from the command line:

$ some-package

The above will fail. Only globally installed packages can be executed by typing their name only.

To fix this, and have it run, you must type the local path:

$ ./node_modules/.bin/some-package

You can technically run a locally installed package by editing your packages.json file and adding that package in the scripts section:

  "name": "whatever",
  "version": "1.0.0",
  "scripts": {
    "some-package": "some-package"

Then run the script using npm run-script (or npm run):

npm run some-package


npx will check whether <command> exists in $PATH, or in the local project binaries, and execute it. So, for the above example, if you wish to execute the locally-installed package some-package all you need to do is type:

npx some-package

Another major advantage of npx is the ability to execute a package which wasn’t previously installed:

$ npx create-react-app my-app

The above example will generate a react app boilerplate within the path the command had run in, and ensures that you always use the latest version of a generator or build tool without having to upgrade each time you’re about to use it.

Related questions:

  1. How to use package installed locally in node_modules?
  2. NPM: how to source ./node_modules/.bin folder?
  3. How do you run a js file using npm scripts?

Solution 2:

npx is a npm package runner (x probably stands for eXecute). The typical use is to download and run a package temporarily or for trials.

create-react-app is an npm package that is expected to be run only once in a project’s lifecycle. Hence, it is preferred to use npx to install and run it in a single step.

As mentioned in the man page https://www.npmjs.com/package/npx, npx can run commands in the PATH or from node_modules/.bin by default.

With some digging, we can find that create-react-app points to a Javascript file (possibly to /usr/lib/node_modules/create-react-app/index.js on Linux systems) that is executed within the node environment. This is simply a global tool that does some checks. The actual setup is done by react-scripts, whose latest version is installed in the project. Refer https://github.com/facebook/create-react-app for more info.

Solution 3:


From https://www.futurehosting.com/blog/npx-makes-life-easier-for-node-developers-plus-node-vulnerability-news/:

Web developers can have dozens of projects on their development
machines, and each project has its own particular set of npm-installed
dependencies. A few years back, the usual advice for dealing with CLI
applications like Grunt or Gulp was to install them locally in each
project and also globally so they could easily be run from the command

But installing globally caused as many problems as it solved. Projects
may depend on different versions of command line tools, and polluting
the operating system with lots of development-specific CLI tools isn’t
great either. Today, most developers prefer to install tools locally
and leave it at that.

Local versions of tools allow developers to pull projects from GitHub
without worrying about incompatibilities with globally installed
versions of tools. NPM can just install local versions and you’re good
to go. But project specific installations aren’t without their
problems: how do you run the right version of the tool without
specifying its exact location in the project or playing around with

That’s the problem npx solves. A new tool included in NPM 5.2, npx is
a small utility that’s smart enough to run the right application when
it’s called from within a project.

If you wanted to run the project-local version of mocha, for example,
you can run npx mocha inside the project and it will do what you

A useful side benefit of npx is that it will automatically install npm
packages that aren’t already installed. So, as the tool’s creator Kat
Marchán points out, you can run npx benny-hill without having to deal
with Benny Hill polluting the global environment.

If you want to take npx for a spin, update to the most recent version
of npm.

Solution 4:

npx runs a command of a package without installing it explicitly.

Use cases:

  • You don’t want to install packages neither globally nor locally.
  • You don’t have permission to install it globally.
  • Just want to test some commands.


npx [options] [-p|--package <package>] <command> [command-arg]...

Package is optional:

npx   -p uglify-js         uglifyjs --output app.min.js app.js common.js
      +----------------+   +--------------------------------------------+
      package (optional)   command, followed by arguments

For example:

Start a HTTP Server      : npx http-server
Lint code                : npx eslint ./src
                         # Run uglifyjs command in the package uglify-js
Minify JS                : npx -p uglify-js uglifyjs -o app.min.js app.js common.js
Minify CSS               : npx clean-css-cli -o style.min.css css/bootstrap.css style.css
Minify HTML              : npx html-minifier index-2.html -o index.html --remove-comments --collapse-whitespace
Scan for open ports      : npx evilscan --port=10-9999
Cast video to Chromecast : npx castnow http://commondatastorage.googleapis.com/gtv-videos-bucket/sample/ForBiggerFun.mp4

More about command:

Solution 5:

NPM is a package manager, you can install node.js packages using NPM

NPX is a tool to execute node.js packages.

It doesn’t matter whether you installed that package globally or locally. NPX will temporarily install it and run it. NPM also can run packages if you configure a package.json file and include it in the script section.

So remember this, if you want to check/run a node package quickly without installing locally or globally use NPX.

npM – Manager

npX – Execute – easy to remember

Solution 6:

Here’s an example of NPX in action: npx cowsay hello

If you type that into your bash terminal you’ll see the result. The benefit of this is that npx has temporarily installed cowsay. There is no package pollution since cowsay is not permanently installed. This is great for one off packages where you want to avoid package pollution.

As mentioned in other answers, npx is also very useful in cases where (with npm) the package needs to be installed then configured before running. E.g. instead of using npm to install and then configure the json.package file and then call the configured run command just use npx instead. A real example:
npx create-react-app my-app