Ultimate Guide to Angular Performance Optimization in 2023

Table of Contents

Introduction

Every user expects their application to load faster and run smoothly, providing a seamless experience. However, it is likely when the application is optimized. And for that, Angular is the best choice as it is a high-performance front-end framework.

It offers numerous tools and techniques that enhance application performance. So, let’s understand how to improve the performance of the Angular application. This blog has covered Angular tips and tricks and the best tools for Angular Performance Optimization that help you speed up your Angular application’s performance.

Strategies for Angular Performance Optimization

Following the best practices and Angular optimization techniques, you can eliminate the typical bottlenecks and upgrade your application performance.

Use of AOT (Ahead-of-Time) Compiler

Angular offers two types of Compilers: Just in time and Ahead of time. Till Angular 8, Angular default compilation mode was Just in Time (JIT). However, since the release of Angular 9, the default compilation has been Ahead of Time(AOT).

It involves compilation during development time and eliminates the need for a deployment bundle. Also, it helps reduce the application’s size, provide time to render individual components and increase application performance.

Additionally, during the application, their template binding errors are identified and fail fast, so the development process becomes faster.

To use AOT, developers can use the Angular CLI command.

Tree Shaking to Reduce Bundle Size

In Angular, Tree Shaking is used to decrease the size of JavaScript’s bundle. Tree shaking removes unused code from the application and shifts it into a smaller, more efficient bundle.

The underlying build system performs it like Angular CLI during the building process. In addition, the build system analyzes the code and detects unused code, functions, or classes not called by the application.

Thus, by removing unused code, the small size of JavaScript helps to load faster and enhance overall performance. However, if you are using Angular CLI, you can make it default.

To enable tree shaking in an Angular application, you can use the following command in the Angular CLI:

Lazy Loading of Modules

Lazy loading is a default feature of Angular to boost performance. It is an Angular technique with numerous feature modules and helps improve the initial load time. Only essential modules are loaded with lazy loading when a user navigates to a particular application section.

It helps load only some applications simultaneously and decreases the load time. Also, the modules are created routes and split apps into smaller chunks, with each chunk containing a specific feature or section.

By implementing lazy loading in the Angular application, you can make the app more responsive and engaging faster. Also, it reduces the amount of data required to be transmitted over the network and server load.

Change Detection Optimization

Change detection can detect when the user’s data has changed or updated. It is one of the primary features of Angular frameworks, and it is essential for maintaining the consistency of an Angular application.

Change detection refers to applying changes to the application’s data model so that the view can be modified accordingly. Change detection has three strategies to overcome: OnPush detection strategy, immutable data structure, and pure pips.

Using OnPush Change Detection Strategy

OnPush is a change detection strategy in Angular and is known as the “checkAlways” strategy. Angular uses the default change detection strategy to check the component’s data model change after every event, such as time, HTTP request, and user inputs.

One of the benefits of a change detection strategy is that it decreases the number of change detection cycles, boosting performance and reducing memory usage. In addition, this strategy instructs Angular only to check changes when the input properties of a component change.

It helps to learn about the application and ensure they use the best practices like lazy loading for optimal performance. The change strategy can identify the user’s data and then update the DOM to demand the changes.

To use a change detection strategy, you can use the following OnPush property:

Immutable Data and Using Pure Pipes

An immutable data structure is valuable for optimizing change detection in Angular applications. It refers to the data that cannot be changed after creation. By using immutability data, developers can ensure that the application’s data model is updated when necessary and helps to improve overall performance.

Pips are divided into categories: Impure and Pure Pipes. Use Pure Pipes transforms data before it is displayed to the users. Not all pipes are created equally regarding the change detection performance. By using pure pipes, you can decrease the number of unnecessary change cycles.

The impure Pipe produces numerous outputs for the same input over time. To define pure pipes, you can use the following:

To define impure pipes, you can use the following properties:

Avoiding Expensive Operations in Templates

Avoiding expensive operations is crucial as it impacts the application’s performance. Also, to avoid operations in templates, you should keep templates as simple as possible to improve performance.

Also, it means that you are avoiding complex logic and computations in templates and moving them to component services. Developers can use this technique to optimize the performance of templates.

Additionally, catching expensive operations can help decrease the same recomputing results numerous times and make it more efficient.

Proper Usage of ngZone

A ngZone service is a powerful tool of Angular for managing the change detection process. However, too much use of ngZone affects your application’s performance. Thus, it is crucial to use it accordingly to restrict unintended consequences.

Using ngZone outside the Angular zone would be beneficial to improve its performance. It is possible by using zone-agnostic API provided by third-party libraries like RxJS. Also, it helps developers to avoid change detection cycles and clean up unnecessary tasks.

Also, this function helps to correct change detection automatically and at the right time. It does not let third-party APIs harm the application’s performance.

Minimizing the Number of HTTP Requests

Each HTTP request made by Angular includes TCP connection establishment, DNS resolution, and TLS negotiation. This will improve Angular performance significantly. Also, one of the best practices to minimize HTTP requests is to use caching.

By caching responses from earlier requests, you can avoid redundant requests and reduce the number of HTTP requests. In addition, combining multiple HTTP requests into a single request can enhance performance optimization in Angular.

Tips for Improving Angular Performance

Knowing strategies is enough for enhancement. Still, the cherry on the top would be implementing the following tips to improve your Angular application performance:

🟠 Reducing the Size of Images and Other Assets

The size of images and other assets can be significant, resulting in more loading times and slow Angular performance. Reducing the size of images and assets optimize application performance and work efficiently.

You can reduce it by compressing images and utilizing tiny CSS and JavaScript files with tools like Compressor.io or TinyPNG. Additionally, you must consider Angular performance optimization techniques such as progressive and lazy loading.

🟠 Using Caching to Improve Loading Times

Another powerful Angular performance optimization technique is using catching to boost loading times. By caching data, you can decrease the number of HTTP requests made to the server and improve application loading time.

Additionally, you can use tools like Angular HTTPClient and Service Workers to implement multiple levels, such as server cache, browser cache, and client-side caching. With a lower loading time, your application can run faster and significantly.

🟠 Minimizing the Number of Third-party Libraries

Too many libraries affect performance tuning in Angular applications. Each library adds value to the application, and sometimes it can negatively impact the performance. Also, each library increases file size and slows down its loading time.

Hence, avoiding using multiple libraries that perform similar or identical functions is ideal. Also, you do not have to depend on a set of libraries to perform particular dependable and overhead tasks.

🟠 Avoiding Unnecessary Code Duplication

In Angular, code duplication leads to inefficient code and negatively impacts application performance. A code duplication increases your application’s file size and creates functionality issues. For Angular app performance optimization, you should avoid unnecessary code duplication and must write clean, efficient code that is maintainable and reusable.

Additionally, for Angular best practices for performance, use Angular’s built-in mechanisms for dependency injection to share functionality between services and components.

🟠 Code Profiling and Analysis

To identify the bottlenecks of performance in Angular applications, it is essential to use code profiling and analysis. You can improve particular tasks by analyzing the code and identifying the areas of inefficiency.

Also, some profiling and analysis tools for improved apps include Angular Angury and Chrome Dev Tools. You can optimize code and improve Angular applications’ performance and user experience using these tools.

Tools for Measuring Angular Performance

Apart from strategies and tips, the following tools help you to measure Angular performance and bring the best results.

1. Chrome DevTools

It is a set of tools and features of the Google Chrome browser that provides analyzing and debugging of Angular applications. It includes memory and CPU profiling features and network analysis to inspect and analyze the Angular performance.

Also, you can use the timeline view to visualize the Angular performance improvements and identify potential bottlenecks in real time. Additionally, the tool allows you to inspect your application’s network activity and render HTML.

2. Lighthouse

The open-source tool from Google helps you audit the performance of Angular applications, best practices accessibility, and SEO. Lighthouse provides a detailed report of the application’s performance with actionable insights that help to optimize speed.

The Lighthouse measures the website or web application’s responsiveness time. It includes performance metrics, such as time to interact, total blocking time, and contentful performance. It can also simulate numerous network conditions to test performance.

3. WebPageTest

It is a free online tool that allows you to test application performance from various locations and browsers worldwide. Using WebPageTest, you can measure the application’s loading speed and detect Angular performance issues.

The tool provides insightful reports on speed, loading time, and render time. WebPageTest provides a wide range of advanced metrics to measure Angular application performance, including time to first byte and paint.

4. Angular Performance Explorer

It is a tool designed to analyze and measure the performance of Angular apps. Angular Performance Explorer provides insights into rendering, change detection, and visual interfaces for exploring the performance metrics of your Angular application.

Also, it includes memory usage, network requests, and CPU for optimizing code and summaries the potential issues along with the solution. The tools also provide recommendations, such as optimizing change detection strategies and lazy loading modules.

Final Word

Frequently Asked Questions (FAQs)

How to fix Angular performance issues?

There are numerous ways of Angular performance optimization in your existing application. But the best way to tune your application is Lazy loading. It allows you to split bundles and modules to reduce memory usage.

How to improve Angular code quality?

The best practice to improve the quality of Angular code is to try centralizing state management, avoid logic out of the module, and use the right Async code.

How to increase page speed in Angular application?

Below are the best possible ways that are worth considering to increase the page speed of your Angular application:

• Decrease HTTP requests
• Decrease the number of server requests to improve the performance of your application.
• Allow Gzip compression to increase page speed.