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Command-line arguments in Node.js

Submitted by: @import:30-seconds-of-code·Mar 2, 2026·

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Problem

When working with Node.js scripts, you might need to access the command-line arguments passed to the script. This can be useful for configuring the script or passing additional information to it. But how can you do that?
Node.js provides the process.argv array, which contains the command-line arguments passed to the Node.js process. The first two elements of the array are the path of the Node.js executable and the file being executed. Let's look at an example to make it clearer:
In order to get only the command-line arguments passed to the script, you can use Array.prototype.slice() to remove the first two elements of the process.argv array. Then, you can use them as needed in your script.
If you need to check if a specific flag is present in the command-line arguments, you can use Array.prototype.every() and Array.prototype.includes() to check if process.argv contains the specified flag. Then, you can use a regular expression to test if the specified flag is prefixed with - or -- and prefix it accordingly.

Solution

// $ node my-script.js --name=John --age=30

process.argv;
/* [
  '/path/to/node',
  '/path/to/my-script.js',
  '--name=John',
  '--age=30'
] */

In order to get only the command-line arguments passed to the script, you can use Array.prototype.slice() to remove the first two elements of the process.argv array. Then, you can use them as needed in your script.
If you need to check if a specific flag is present in the command-line arguments, you can use Array.prototype.every() and Array.prototype.includes() to check if process.argv contains the specified flag. Then, you can use a regular expression to test if the specified flag is prefixed with - or -- and prefix it accordingly.

Code Snippets

// $ node my-script.js --name=John --age=30

process.argv;
/* [
  '/path/to/node',
  '/path/to/my-script.js',
  '--name=John',
  '--age=30'
] */

const getCmdArgs = () => process.argv.slice(2);

// $ node my-script.js --name=John --age=30
getCmdArgs(); // ['--name=John', '--age=30']

const hasFlags = (...flags) =>
  flags.every(flag =>
    process.argv.includes(/^-{1,2}/.test(flag) ? flag : '--' + flag)
  );

// node my-script.js -s --test --cool=true
hasFlags('-s'); // true
hasFlags('--test', 'cool=true', '-s'); // true
hasFlags('special'); // false

Context

From 30-seconds-of-code: command-line-arguments

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