Detect Dark Mode Preference with JavaScript

By  on  

Seemingly every website, dapp, and app offers a dark mode preference, and thank goodness. Dark mode is especially useful when I'm doing late night coding, or even worse, trading into altcoins. I'm presently working on implementing a dark theme on MetaMask and it got me to thinking: is there a way we can default to dark mode if the user's operating system also defaults to dark mode?

You can determine if the user's operating system prefers dark mode with one quick line of code:

const prefersDarkMode = window.matchMedia("(prefers-color-scheme:dark)").matches; // true

This code snippet takes advantage of the CSS prefers-color-scheme media query with JavaScript's matchMedia API.

From a user experience standpoint, you'll need to be careful in using this snippet. This method is great for setting a default for new users without changing the value for existing users.

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
    5 Awesome New Mozilla Technologies You’ve Never Heard Of

    My trip to Mozilla Summit 2013 was incredible.  I've spent so much time focusing on my project that I had lost sight of all of the great work Mozillians were putting out.  MozSummit provided the perfect reminder of how brilliant my colleagues are and how much...

Incredible Demos

Discussion

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