How can you optimize network requests for better performance?

TL;DR

To optimize network requests for better performance, you can minimize the number of requests, use caching, compress data, and leverage modern web technologies like HTTP/2 and service workers. For example, you can combine multiple CSS files into one to reduce the number of requests, use Cache-Control headers to cache static assets, and enable Gzip compression on your server to reduce the size of the data being transferred.

Minimize the number of requests

Reducing the number of network requests can significantly improve performance. Here are some strategies:

Combine files: Merge multiple CSS or JavaScript files into a single file.
Image sprites: Combine multiple images into a single sprite sheet and use CSS to display the correct part of the image.
Inline small assets: Use data URIs to inline small images or fonts directly into your CSS or HTML.

Use caching

Caching can reduce the need to make network requests for resources that have not changed:

HTTP caching: Use Cache-Control and ETag headers to control how and when resources are cached by the browser.
Service workers: Implement service workers to cache assets and API responses, allowing your app to work offline and load faster on subsequent visits.

Compress data

Reducing the size of the data being transferred can speed up network requests:

Gzip/Brotli compression: Enable Gzip or Brotli compression on your server to compress HTML, CSS, and JavaScript files.
Minification: Minify CSS, JavaScript, and HTML files to remove unnecessary characters and reduce file size.

Leverage modern web technologies

Modern web technologies can help optimize network performance:

HTTP/2: Use HTTP/2 to take advantage of multiplexing, header compression, and server push, which can reduce latency and improve load times.
CDNs: Use Content Delivery Networks (CDNs) to serve static assets from locations closer to the user, reducing latency.

Optimize images

Images often account for a large portion of the data transferred:

Responsive images: Use the srcset attribute to serve different image sizes based on the user's device.
Image formats: Use modern image formats like WebP or AVIF, which offer better compression than traditional formats like JPEG or PNG.
Lazy loading: Implement lazy loading to defer loading images until they are needed.

Reduce payload size

Reducing the amount of data sent in each request can improve performance:

API optimization: Optimize API responses to include only the necessary data.
GraphQL: Use GraphQL to request only the specific data needed by the client.

How can you optimize network requests for better performance?

TL;DR