The definitive source of the best
JavaScript libraries, frameworks, and plugins.

  • ×

    Modernizr is a JavaScript library that detects HTML5 and CSS3 features in the user’s browser.
    Filed under  › 

    • 🔾92%Overall
    • 23,223
    • 7.1 days
    • 🕩3010
    • 👥41

    Modernizr Build Status Inline docs

    Modernizr is a JavaScript library that detects HTML5 and CSS3 features in the user’s browser.

    Modernizr tests which native CSS3 and HTML5 features are available in the current UA and makes the results available to you in two ways: as properties on a global Modernizr object, and as classes on the <html> element. This information allows you to progressively enhance your pages with a granular level of control over the experience.

    This project adheres to the Open Code of Conduct. By participating, you are expected to honor this code.

    New Asynchronous Event Listeners

    Often times people want to know when an asynchronous test is done so they can allow their application to react to it. In the past, you've had to rely on watching properties or <html> classes. Only events on asynchronous tests are supported. Synchronous tests should be handled synchronously to improve speed and to maintain consistency.

    The new API looks like this:

    // Listen to a test, give it a callback
    Modernizr.on('testname', function( result ) {
      if (result) {
        console.log('The test passed!');
      else {
        console.log('The test failed!');

    We guarantee that we'll only invoke your function once (per time that you call on). We are currently not exposing a method for exposing the trigger functionality. Instead, if you'd like to have control over async tests, use the src/addTest feature, and any test that you set will automatically expose and trigger the on functionality.

    Getting Started

    • Clone or download the repository
    • Install project dependencies with npm install

    Test suite

    Run the test suite

    Building Modernizr v3

    To generate everything in 'config-all.json':

    npm install
    ./bin/modernizr -c lib/config-all.json
    //outputs to ./modernizr.js

    To run tests on the console (in phantom):

    grunt test

    To run tests in the browser:

    grunt browserResults

    then visit http://localhost:9090/test/unit.html for unit test results

    or visit http://localhost:9090/test/index.html to see which features that browser supports

    To see the build tool:

    • checkout the code
    • install all your gems and bundles and jekyll
    • jekyll
    • serve ./_sites
    • visit /download
    • It should be just a big list of things you can build with no frills.

    API Reference

    Modernizr can be used programmatically via npm:

    var modernizr = require("modernizr");


    A build method is exposed for generating custom Modernizr builds. Example:

    var modernizr = require("modernizr");{}, function (result) {
      console.log(result); // the build

    The first parameter takes a JSON object of options and feature-detects to include. See lib/config-all.json for all available options.

    The second parameter is a function invoked on task completion.


    MIT License

    Show All