/lazy-img

A bulletproof lazy image loader.

Primary LanguageJavaScriptApache License 2.0Apache-2.0

lazy-img

A performant & accessible responsive lazy image loader for Cloudinary. Configure your grid, and the loader will do the rest, snapping the image sizes to your defined grid.

Google will index the valid default image in the src even it doesn't run JS on your site, while your browser will load only the blank 1×1 .gif present in the srcset.

The ratio is used for setting up aspect ratio wrappers for the <img> to prevent page jumps.

Example usage

Codepen demo

Prostoria.eu (production)

Example markup:

<img class="js-lazy-img"
  src="https://res.cloudinary.com/{accountName}/image/upload/w_1440,c_fill,f_auto,q_auto/{src}"
  srcset="data:image/gif;base64,R0lGODlhAQABAIAAAP///////yH5BAEKAAEALAAAAAABAAEAAAICTAEAOw"
  data-src="{src}"
  alt="">

Background image loading a separate data-src attribute. Avoid setting the file extension so that Cloudinary can serve the best file format your browser supports. A full list of Cloudinary transformations can be found here.