Skip to main content
Dublin Library

The Publishing Project

Generating UUIDs with Node


UUIDs (Universally Unique IDentifier) are also known as GUIDs (Globally Unique IDentifier). A UUID is 128 bits long and can guarantee uniqueness across space and time.

UUIDs are defined in RFC 4122.

This post will work in two ways of generating UUID V4 strings: Using the UUID package and the randomUUID method of the native Node Crypto package.

The native way #

Since Node 15.6.0, Node's crypto module provides a method for generating v4 UUIDs.

We first import the method from the crypto module.

import {
} from 'crypto';

We then call the method to generate a UUID using the randomUUID() method. We assign the result to a variable.

We can then use it wherever we need. For this example, we log the UUID value to the console.

const id = randomUUID();
// -> 2f3476fc-0795-40e8-884a-588701b29540

With the UUID package #

Before Node introduced the native version, the best way to generate UUID strings is using a third-party package like uuid.

We first install the package; this assumes you have started the project with npm init or npm init --yes.

npm install uuid

We then import the v4 method from uuid. We use an alias to point to uuidv4 for clarity.

import { v4 as uuidv4 } from 'uuid';

We use the alias (uuidv4) to generate a UUID and store it in a variable. We can then use it wherever we need to.

const myID = uuidv4();

Final Notes #

crypto.randomUUID() was backported to Node 14.17.0 and later. If you need an earlier version of Node, your best bet is to use the uuid package.

To use imports in Node, I changed file extension from .js to .mjs.

Edit on Github