JavaScript Numeric Separators

By  on  

Writing good code is important -- writing code that's easily human readable is a next level skill. It's not often that APIs are introduced whose seemingly only useful function is making code more readable, but let me introduce you to JavaScript numeric separators: an API that lets developers use underscores to make numbers more readable!

Consider the following number in your code:

// No commas for numbers in JavaScript
const oneHundredThousand = 100000;

Large numbers have always been difficult to mentally parse for engineers, so using underscores to make code more readable is a total win:

const oneMillion = 1_000_000; // 1000000
const decimals = 1_000_00.01_02_03 // 100000.010203

The only real rule with numeric separators is that the number cannot start or end with an underscore.

Numeric separators within JavaScript seem like spec creators gifting developers a feature. As an engineer, I'll take all I can get. You never stop learning in the world of JavaScript!

Recent Features

Incredible Demos

  • By
    JavaScript Battery API

    Mozilla Aurora 11 was recently released with a bevy of new features. One of those great new features is their initial implementation of the Battery Status API. This simple API provides you information about the battery's current charge level, its...

  • By
    MooTools FontChecker Plugin

    There's a very interesting piece of code on Google Code called FontAvailable which does a jQuery-based JavaScript check on a string to check whether or not your system has a specific font based upon its output width. I've ported this functionality to MooTools. The MooTools...

Discussion

    Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!