How to generate unique ID with node.js

Install NPM uuid package (sources: https://github.com/kelektiv/node-uuid):

npm install uuid

and use it in your code:

var uuid = require('uuid');

Then create some ids ...

// Generate a v1 (time-based) iduuid.v1(); // -> '6c84fb90-12c4-11e1-840d-7b25c5ee775a'// Generate a v4 (random) iduuid.v4(); // -> '110ec58a-a0f2-4ac4-8393-c866d813b8d1'

** UPDATE 3.1.0
The above usage is deprecated, so use this package like this:

const uuidv1 = require('uuid/v1');uuidv1(); // -> '6c84fb90-12c4-11e1-840d-7b25c5ee775a' const uuidv4 = require('uuid/v4');uuidv4(); // -> '110ec58a-a0f2-4ac4-8393-c866d813b8d1' 

** UPDATE 7.x
And now the above usage is deprecated as well, so use this package like this:

const {   v1: uuidv1,  v4: uuidv4,} = require('uuid');uuidv1(); // -> '6c84fb90-12c4-11e1-840d-7b25c5ee775a' uuidv4(); // -> '110ec58a-a0f2-4ac4-8393-c866d813b8d1' 

The fastest possible way to create random 32-char string in Node is by using native crypto module:

const crypto = require("crypto");const id = crypto.randomBytes(16).toString("hex");console.log(id); // => f9b327e70bbcf42494ccb28b2d98e00e

edit: shortid has been deprecated. The maintainers recommend to use nanoid instead.

Another approach is using the shortid package from npm.

It is very easy to use:

var shortid = require('shortid');console.log(shortid.generate()); // e.g. S1cudXAF

and has some compelling features:

ShortId creates amazingly short non-sequential url-friendly uniqueids. Perfect for url shorteners, MongoDB and Redis ids, and any otherid users might see.

• By default 7-14 url-friendly characters: A-Z, a-z, 0-9, _-
• Non-sequential so they are not predictable.
• Can generate any number of ids without duplicates, even millions per day.
• Apps can be restarted any number of times without any chance of repeating an id.