Speedometer is a cutting-edge browser benchmark that measures the responsiveness of web applications by simulating user interactions. With its demo web apps, Speedometer adds to-do items in TodoMVC, giving you a real-time snapshot of your app's performance.
The Importance of Viewport Size
Before we dive into the details, please make sure your browser window is at least 850px by 650px for most accurate results. This ensures that your performance metrics are not skewed by an undersized viewport.
What Speedometer Measures
Speedometer tests a browser's Web app responsiveness by timing simulated user interactions. It simulates adding, completing, and removing to-do items in TodoMVC, using multiple examples to gauge the impact of different JavaScript frameworks on app performance. By analyzing these scenarios, you'll gain valuable insights into how your app will perform under various conditions.
A Holistic Approach
Speedometer doesn't just stop at measuring synchronous operations; it also takes into account asynchronous work, which can greatly impact app responsiveness. In fact, some modern JavaScript frameworks like Vue.js and Preact use asynchronous DOM API calls to optimize performance. Speedometer approximates the run time of these asynchronous operations, giving you a comprehensive view of your app's user experience.
Limitations
While Speedometer provides valuable insights into app performance, it's essential to remember that user-driven actions like mouse movements and keyboard input cannot be accurately emulated in JavaScript. Additionally, Speedometer doesn't measure concurrent asynchronous work that doesn't directly impact the UI thread, as this tends not to affect app responsiveness.
Target Audience
Note that Speedometer should not be used as a way to compare the performance of different JavaScript frameworks, as workload differs greatly between each framework. Instead, use Speedometer to optimize your app's user experience and ensure it provides the best possible interactions for users.
By leveraging Speedometer's powerful benchmarking capabilities, you'll be able to identify areas for improvement and deliver an exceptional app user experience that keeps users engaged and coming back for more.