Using `import` Statements in Node.js

Jun 24, 2020

Node.js 12 introduced support for the import statement behind a --experimental-modules flag and a package.json configuration option. Node.js 14 removes the need for the --experimental-modules flag, but you still need to configure your package.json. Here's how you can use ES6 imports in Node.


Suppose you have two JavaScript files: index.js and test.js. The test.js file exports a simple function:

export default function test() {
  console.log('Hello, World');

The index.js file imports the test.js file:

import test from './test.js';


When using ES6 imports in Node.js, you must put the file extension .js, except for so-called "bare paths" for importing packages your ./node_modules. Putting import test from './test' will throw an error.

To run index.js, you need to create a package.json file with a type property set to "module". Below is a minimal package.json file to enable running index.js in Node.js 14, or Node.js 12 with --experimental-modules.

{ "type": "module" }

Importing NPM Modules

To import a module you installed via npm, you can import the package name. The below example shows how you can import Mongoose using ES6 imports.

import mongoose from 'mongoose';

console.log(mongoose.version); // 5.9.19

Node.js takes care of the quirks of interopability between CommonJS (Node's require()) and ESM (ES6 import). So even though Mongoose 5 uses CommonJS internally, your project can import it as it would any ESM module.

Note that bare paths only work for the top-level npm module, not for files in the npm module. For example, you can get Lodash's omit() function in CommonJS by calling require('lodash/omit'). Using ESM imports, you need to add .js at the end.

import omit from 'lodash/omit.js';

console.log(omit({ a: 1, b: 2 }, ['b'])); // { a: 1 }

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