Pen Settings

CSS Base

Vendor Prefixing

Add External Stylesheets/Pens

Any URL's added here will be added as <link>s in order, and before the CSS in the editor. If you link to another Pen, it will include the CSS from that Pen. If the preprocessor matches, it will attempt to combine them before processing.

+ add another resource

You're using npm packages, so we've auto-selected Babel for you here, which we require to process imports and make it all work. If you need to use a different JavaScript preprocessor, remove the packages in the npm tab.

Add External Scripts/Pens

Any URL's added here will be added as <script>s in order, and run before the JavaScript in the editor. You can use the URL of any other Pen and it will include the JavaScript from that Pen.

+ add another resource

Use npm Packages

We can make npm packages available for you to use in your JavaScript. We use webpack to prepare them and make them available to import. We'll also process your JavaScript with Babel.

⚠️ This feature can only be used by logged in users.

Code Indentation


Save Automatically?

If active, Pens will autosave every 30 seconds after being saved once.

Auto-Updating Preview

If enabled, the preview panel updates automatically as you code. If disabled, use the "Run" button to update.

HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

  <h1>Demonstrating <code>fm=json</code> parameter to set aspect ratios based on original image sizes using imgix.</h1>
  <p>Originally, we cropped all of our images to fit within the same aspect ratio. Originals were set to <code>w=300</code>, <code>h=200</code>, and <code>fit=crop</code>.</p>
    <img src="https://assets.imgix.net/examples/octopus.jpg?w=300&h=200&fit=crop">
    <img src="https://assets.imgix.net/examples/espresso.jpg?w=300&h=200&fit=crop">
    <img src="https://miguel.imgix.net/imgix/flower.jpg?w=300&h=200&fit=crop">
    <img src="https://assets.imgix.net/examples/kayaks.png?w=300&h=200&fit=crop">
  <p>Eventually, we decided that we wanted to maintain the aspect ratios of the source images. We can now do that using the <a href="https://www.imgix.com/docs/reference/format#param-fm">imgix JSON Output Format</a>. In this pen, we use JavaScript to read metadata about an image then set a max dimensions with the longest edge of 300px and a 16:9 ratio.</p>
    <img data-src="https://assets.imgix.net/examples/octopus.jpg" src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="imgix-item">
    <img data-src="https://assets.imgix.net/examples/espresso.jpg" src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="imgix-item">
    <img data-src="https://miguel.imgix.net/imgix/flower.jpg" src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="imgix-item">
    <img data-src="https://assets.imgix.net/examples/kayaks.png" src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="imgix-item">
  Without storing any information server-side, we're able to build rich displays of our images based on their natural aspect ratios. This opens up a whole new way of working with images on imgix.

<p>imgix is a hosted service that takes your existing static images and turns them into dynamic, responsive images that you can deliver to any device, under any conditions. It’s free to sign up at <a href="https://imgix.com">imgix.com</a>.</p>
  text-align: center;

image-container {
  width: auto;
  display: inline-block;
  vertical-align: top;
  max-width: 1280px;
  height: auto;
  margin: 20px 0 20px 20px;
  img {
    max-width: 100%;

h1, p{
  font-family:'Helvetica Neue', Helvetica, Arial, sans;
  max-width: 480px;
  margin: 1em auto 1em auto;
  text-align: left;
  line-height: 1.4;
  color: #333;

  line-height: 1.2;
  margin-top: 2em;
  margin-bottom: 0;

  font-family: "Lucida Console",monaco,mono;
  color: #4b7498;
              // Demonstrate the use of the `fm=json` parameter to resize images
// to a certain aspect ratio, using ES6.

let ratio = 16 / 9;
let maxSize = 300;

let placeImages = function() {
	jQuery('.imgix-item').each((i, value) => {
    let $elem = jQuery(value);    
    // We pull down the image specific by the 'data-src' attribute
    // of each .imgix-item, but append the "?fm=json" query string to it.
    // This instructs imgix to return the JSON Output Format instead of 
    // a manipulated image.
    let url = new imgix.URL($elem.attr('data-src'), { fm: "json" }).getUrl();
		jQuery.ajax(url).success((data) => {
      let newWidth, newHeight;

      // Next, we compute the new height/width params for 
      // each of our images.
      if (data.PixelHeight > data.PixelWidth) {
        newHeight = maxSize;
        newWidth = Math.ceil(newHeight / ratio);
      } else {
        newWidth = maxSize;
        newHeight = Math.ceil(newWidth / ratio);

      // Now, we apply these to our actual images, setting the 'src'
      // attribute for the first time.
      $elem.get(0).src = new imgix.URL($elem.attr('data-src'), { 
        w: newWidth, 
        h: newHeight, 
        fit: "crop" 

🕑 One or more of the npm packages you are using needs to be built. You're the first person to ever need it! We're building it right now and your preview will start updating again when it's ready.