Generate a Random ID or String in Node.js or JavaScript

Generating random IDs or strings in Node.js or JavaScript is useful in various situations. For example, when generating an application or encryption key you want to create random strings with a minimal chance of duplication or collision.

This tutorial shows you two ways to create a random string with JavaScript.

Node.js Series Overview

  1. String Replace All Appearances
  2. Remove All Whitespace From a String in JavaScript
  3. Generate a Random ID or String in Node.js or JavaScript
  4. Remove Extra Spaces From a String in JavaScript or Node.js
  5. Remove Numbers From a String in JavaScript or Node.js
  6. Get the Part Before a Character in a String in JavaScript or Node.js
  7. Get the Part After a Character in a String in JavaScript or Node.js
  8. How to Check if a Value is a String in JavaScript or Node.js
  9. Check If a String Includes All Strings in JavaScript/Node.js/TypeScript
  10. Check if a Value is a String in JavaScript and Node.js
  11. Limit and Truncate a String to a Given Length in JavaScript and Node.js
  12. Split a String into a List of Characters in JavaScript and Node.js
  13. How to Generage a UUID in Node.js
  14. Reverse a String in JavaScript or Node.js
  15. Split a String into a List of Lines in JavaScript or Node.js
  16. Split a String into a List of Words in JavaScript or Node.js
  17. Detect if a String is in camelCase Format in Javascript or Node.js
  18. Check If a String Is in Lowercase in JavaScript or Node.js
  19. Check If a String is in Uppercase in JavaScript or Node.js
  20. Get the Part After First Occurrence in a String in JavaScript or Node.js
  21. Get the Part Before First Occurrence in a String in JavaScript or Node.js
  22. Get the Part Before Last Occurrence in a String in JavaScript or Node.js
  23. Get the Part After Last Occurrence in a String in JavaScript or Node.js
  24. How to Count Words in a File
  25. How to Shuffle the Characters of a String in JavaScript or Node.js
  26. Append Characters or Words to a String in JavaScript or Node.js (Coming soon)
  27. Check if a String is Empty in JavaScript or Node.js (Coming soon)
  28. Ensure a String Ends with a Given Character in JavaScript or Node.js (Coming soon)
  29. Left-Trim Characters Off a String in JavaScript or Node.js (Coming soon)
  30. Right-Trim Characters Off a String in JavaScript or Node.js (Coming soon)
  31. Lowercase the First Character of a String in JavaScript or Node.js (Coming soon)
  32. Uppercase the First Character of a String in JavaScript or Node.js (Coming soon)
  33. Prepend Characters or Words to a String in JavaScript or Node.js (Coming soon)
  1. Get Number of Seconds Since Epoch in JavaScript
  2. Get Tomorrow’s Date in JavaScript
  3. Increase a Date in JavaScript by One Week
  4. Add Seconds to a Date in Node.js and JavaScript
  5. Add Month(s) to a Date in JavaScript or Node.js
  6. Add Week(s) to a Date in JavaScript or Node.js
  7. Get the Current Year in JavaScript or Node.js
  8. How to Get a UNIX Timestamp in JavaScript or Node.js
  9. How to Convert a UNIX Timestamp to a Date in JavaScript or Node.js
  10. Add Days to a Date in JavaScript or Node.js
  11. Get Yesterday's Date in JavaScript or Node.js
  12. Add Minutes to a Date in JavaScript or Node.js (Coming soon)
  13. Add Hours to a Date in JavaScript or Node.js (Coming soon)
  14. Check If a Date Is Today in JavaScript or Node.js (Coming soon)
  15. Check If a Date is Tomorrow in JavaScript or Node.js (Coming soon)
  16. Check If a Date is Yesterday in JavaScript or Node.js (Coming soon)
  17. How to Format a Date YYYY-MM-DD in JavaScript or Node.js (Coming soon)

1. Use the @supercharge/strings Package

The @supercharge/strings package is a helpful hand when working with strings. It also comes with a method to generate a random string. At first, you must install the package as a dependency in your project:

npm i @supercharge/strings  

Generating a random string using @supercharge/strings is pretty straightforward: import the package and call the static .random() method creating a random, URL-friendly string value:

const Str = require('@supercharge/strings')

const random = Str.random()  
// 'zONHF73w_4M3cmv7GZpXG'

const random_WithFiftySymbols = Str.random(50)  
// 'iO3quoYg265hlzq30E8RelQc0LOKle4R0yk6CMbgeHgGNcm_mR'

The generated string is URL-friendly because the package uses an alphabet that contains a well-defined symbol set to avoid side-effects, like the backslash as an escaping character.

The random string contains 21 symbols by default. You can customize the size by passing a number as an argument to Str.random(size).

Pro - generates URL-friendly, random strings - customizable the string length - expressive interface

Contra - extra dependency for your project

2. Use Node.js Crypto

Another option is the usage of Node.js’ crypto module. The Crypto.randomBytes() method generates cryptographically strong pseudo-random data for a given number of bytes. You may then transform the random data to a string value and slice it to comply with the given size:

const Crypto = require('crypto')

function randomString(size = 21) {  
  return Crypto
    .randomBytes(size)
    .toString('base64')
    .slice(0, size)
}

console.log(  
  randomString()
)
// '/VuPgyBlk/aZjPADhMqQk'

Be careful when converting the random data to a base64 string because this string may contain characters like the forward-slash which could have side effects in your app.

Pro - native Node.js functionality - customizable the string length - generates a URL-friendly string when using .toString('hex')

Contra - no URL-friendly when using .toString('base64‘) because it may contain chars like a forward slash (/) - using .toString('hex') reduces the alphabet to numbers and the lowercase characters a-e

Which Way Should You Go?

We prefer the @supercharge/strings package to avoid any issues with symbols that may cause issues in our applications.

If you want to avoid an external dependency, use the Node.js crypto module.


Mentioned Resources

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