How to Optimize Your ASP.NET Application for Improved Performance

If you want your ASP.NET application to perform well, you need to optimize it for speed, responsiveness, and user experience. Performance optimization is critical for factors like fast page load times, improved response efficiency, and happy users. In this article, I'll provide several tips and tricks to help you optimize performance in ASP.NET Core.

Use Response Compression in Your ASP.NET Application

You can use ASP.NET Core's built-in response compression middleware to compress the response data and reduce the amount of data that needs to be transferred over the network. To use response compression, add the following code to your application's Startup.cs file:

services.AddResponseCompression(options =>
    options.EnableForHttps = true;


🖼️ Optimize Images in Your ASP.NET Application:

Images can be a major contributor to page bloat and slow load times. Here are some tips to optimize images:

🖌️ Use a tool like ImageOptim or to compress and optimize images.

🖼️ Specify the width and height of images in HTML so the browser can allocate space for them before they load.

📝 Use alt attributes to provide descriptive text for images, which can improve accessibility and also help with SEO.

📜 Use lazy loading for images that are below the fold, meaning they're not visible on the initial screen view. You can use libraries like Vanilla LazyLoad to implement lazy loading.

📱 Use responsive images to serve different image sizes to different devices. This can improve page load times by reducing the size of images that are displayed on smaller devices.

💻 Example:

    <source media="(min-width: 650px)" data-srcset="image.webp">
    <source media="(min-width: 465px)" data-srcset="image_small.webp">
    <img src="placeholder.png" data-src="image.webp" alt="Image" width="100" height="100" class="lazy" />
var lazyLoadInstance = new LazyLoad();

🧱 Optimize HTML in Your ASP.NET Application:

The structure and organization of HTML can affect the page speed. Here are some tips to optimize HTML:

📝 Use the heading tags (h1, h2, h3, etc.) in a logical and sequential order.

🔩 Use the "defer" attribute for script tags that don't need to be executed immediately. This can improve the page load times by delaying the execution of scripts until after the page has rendered.

🔩 Use the "async" attribute for script tags that can be executed asynchronously. This can further improve the page load times by allowing scripts to be downloaded and executed simultaneously.

🧱 Use semantic HTML elements (like nav, section, and article) to provide additional structure and meaning to the page.

🎨 Optimize CSS and JavaScript in Your ASP.NET Application:

CSS and JavaScript files can be a major contributor to the page load times. Here are some tips to optimize CSS and JavaScript in your ASP.NET application:

🔨 Minify and concatenate CSS and JavaScript files to reduce their size.

🔩 Use the "defer" or "async" attributes for script tags to delay or asynchronously load scripts.

🔡 Use system fonts in Your ASP.NET Application:

Loading custom fonts can be slow and increase page load times. Using system fonts can improve page speed by allowing the browser to use fonts that are already installed on the user's device.

🖼️ Use Placeholders and Progress Indicators in Your ASP.NET Application:

To improve the perceived performance of your website, you can use placeholders and progress indicators for slow-loading sections of your page. You can use JavaScript to load these sections after the initial page load.

💻 Example:

<div id="placeholder" data-url="/slow-loading-content">
const placeholder = document.querySelector('#placeholder');
    .then(response => response.text())
    .then(html => placeholder.innerHTML = html);

🔗 Use the Appropriate Link Text and ARIA Labels:

When using links, use appropriate link texts that accurately describe the content of the linked page. This can improve the accessibility and also help with SEO.

ARIA labels should also be used to provide additional context for links. This can also improve the accessibility and help with SEO.

💻 Example:

<a href="" aria-label="Go to Example">Example</a>
<a href="" aria-label="Go to Another Example">Another Example</a>

🌐 Optimize the Third-party Resources in Your ASP.NET Application:

Third-party resources like social media widgets and advertising scripts can slow down the page load times. Here are some tips to optimize third-party resources:

🔩 Use asynchronous scripts when possible.

🔍 Only load third-party resources that are necessary for the page.

By following these optimization techniques, you can significantly improve the page speed of your ASP.NET Core web application.

Optimized Web Applications with ABP Framework?

ABP Framework offers an opinionated architecture to build enterprise software solutions with ASP.NET Core best practices on top of the .NET and the ASP.NET Core platforms. It is also a powerful infrastructure to help you develop low-effort web-optimized applications. It provides the fundamental web application infrastructure, production-ready dotnet startup templates, modules, core ui themes, tooling, guides and documentation to implement that ASP.NET core architecture properly and automate the details and repetitive work as much as possible.

If you are starting a new ASP.NET Core project and want a fast website now...