Lazy is a jQuery plugin designed to improve website performance by lazy-loading images and other assets. It delays the loading of certain elements until they are needed, which can significantly reduce initial page load times and improve the user experience.


  1. Image Lazy Loading: Load images only when they enter the viewport, saving bandwidth and improving load times.
  2. Asset Preloading: Delay the loading of non-critical assets like scripts, stylesheets, and videos.
  3. Customizable Thresholds: Adjust the triggering point at which lazy-loading occurs.
  4. Responsive Design: Works seamlessly across various screen sizes and devices.
  5. Supports Various Content Types: Not limited to images, can be applied to various content elements.


  • Faster Loading: Reduces initial page load times, especially for pages with numerous images and assets.
  • Bandwidth Savings: Minimizes unnecessary data transfers, saving bandwidth for users.
  • Improved UX: Provides a smoother browsing experience by loading content on-demand.
  • SEO-Friendly: Helps improve page speed, which can positively impact search engine rankings.


Getting Started

To get started with Lazy, include jQuery and the Lazy library in your project:

<!-- jQuery library -->
<script src=""></script>
<!-- Lazy JS -->
<script src="path_to_lazy/jquery.lazy.min.js"></script>

Advanced Examples

Basic Image Lazy Loading:


Lazy Loading with Custom Threshold:

  threshold: 200, // Load images 200 pixels before they enter the viewport

Lazy Loading with Fade-in Effect:

  effect: 'fadeIn', // Apply a fade-in effect when images load

Lazy Loading for Background Images:

  chainable: false, // Prevent elements from loading one after the other

Lazy Loading for Videos:

  enableThrottle: true, // Enable throttling for smoother video loading

The Lazy jQuery plugin is a valuable tool for web developers looking to optimize their websites for faster loading times and improved user experiences. By delaying the loading of images and assets until they are needed, Lazy helps reduce bandwidth usage and enhances overall website performance.