Popular:
 Building Resilient Systems on AWS: Learn how to design and implement a resilient, highly available, fault-tolerant infrastructure on AWS.

Detect Unmatched CSS Selectors with Helium

By  on  

One thing I can't stand is extra code.  Whether it's an extra CSS or JavaScript file that's been included by the page, bloated HTML, or unoptimized images, we're making our millions of of desktop and mobile visitors pay for our laziness and mistakes.  A great tool called Helium is available to help developers detect selectors in their stylesheets that are unmatched or malformed.  Let me show you how it works!

Get Helium

Start by including the script in your page and initializing Helium upon load:

<script type="text/javascript" src="js/lib/helium-css/helium.js" onload="helium.init()" async></script>

As soon as the page is loaded, the developer is presented with a textarea with which they may type page URLs to test.  These pages are then loaded and a report is generated, detailing the unused selectors, malformed selectors, and pseudo-selectors which should be tested manually:

Helium CSS Textarea

Helium CSS Result

Get Helium

Helium is an excellent tool for identifying legacy and unnecessary CSS.  The information provided by Helium allows developers to remove unused CSS or better segment site CSS.  This tool is the perfect utility for developers looking to quickly optimize their CSS code.  In fact, I've not seen a tool so easy to implement and use.  Let me know if you agree!

Request Metrics real user monitoring
Request Metrics real user monitoring
Request Metrics real user monitoring
Request Metrics real user monitoring

Recent Features

  • By
    CSS Animations Between Media Queries

    CSS animations are right up there with sliced bread. CSS animations are efficient because they can be hardware accelerated, they require no JavaScript overhead, and they are composed of very little CSS code. Quite often we add CSS transforms to elements via CSS during...

  • By
    CSS @supports

    Feature detection via JavaScript is a client side best practice and for all the right reasons, but unfortunately that same functionality hasn't been available within CSS.  What we end up doing is repeating the same properties multiple times with each browser prefix.  Yuck.  Another thing we...

Incredible Demos

  • By
    CSS Kwicks

    One of the effects that made me excited about client side and JavaScript was the Kwicks effect.  Take a list of items and react to them accordingly when hovered.  Simple, sweet.  The effect was originally created with JavaScript but come five years later, our...

  • By
    MooTools: Set Style Per Media

    I'd bet one of the most used MooTools methods is the setStyle() method, which allows you to set CSS style declarations for an element. One of the limitations of MooTools' setStyle() method is that it sets the specific style for all medias.

Discussion

  1. Adrian

    Did you know about mincss, written by our own Peterbe? It seem to serve the same purpose, see http://www.peterbe.com/plog/mincss

  2. PH

    Does it do the same job as CSS Usage ? (Firebug extension)

    • BlaineSch

      PH, this tool appears to support checking selectors across multiple pages. CSS Usage is current page only.

  3. BlaineSch

    PH, this tool appears to support checking selectors across multiple pages. CSS Usage is current page only.

  4. Lovely

    Very interesting tools , i will try it now.

    Thank you

  5. Chris

    It’s a handy tool apparently but not a lot of people are using it? It is not efficient enough, or.. I haven’t tried it yet.

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