stats.js is a JavaScript library designed to provide a simple yet effective way to monitor the performance of your code. It focuses on essential metrics – FPS (frames per second), millisecond (MS) elapsed time, and memory usage (MB) – without overwhelming the user. The primary goal is to offer a focused, readily accessible performance overview.

Repository Overview

This project is maintained by mrdoob and is part of the github.com/mrdoob/stats.js repository. It’s available on GitHub and offers a straightforward approach to monitoring JavaScript application performance.

Key Features

  • FPS (Frames Per Second): Displays the current frame rate, offering a visual representation of rendering speed. A higher FPS indicates better performance.
  • MS (Milliseconds): Shows the elapsed time needed to render a single frame, guiding developers to optimize rendering tasks.
  • MB (Megabytes): Provides a quick estimate of allocated memory, allowing users to identify potential memory leaks.
  • Custom Panel Support: Allows users to easily add their own monitoring metrics – essential for specific applications.

Installation

To use stats.js, simply include the library in your JavaScript project:
JAVASCRIPT
var stats = require('stats.js');
stats.showPanel(1);

Usage

JAVASCRIPT
var stats = new Stats();
stats.showPanel(1);
document.body.appendChild(stats.dom);

function animate() {
    stats.begin();

    // Monitor code here
    // Example:  Adding a simple calculation.
    console.log("Animation started.");
    stats.end();
    requestAnimationFrame(animate);
}

requestAnimationFrame(animate);

Benefits

stats.js offers a crucial, low-maintenance solution for quickly assessing the performance of a web application. Its simplicity makes it an excellent choice for developers focused on immediate performance analysis without complex instrumentation.

Why this matters

In a rapidly evolving JavaScript environment, monitoring performance is critical for identifying bottlenecks and optimizing application speed. stats.js directly contributes to this effort by offering a focused and readily implementable toolset for assessing the basic performance of the application.

Conclusion

stats.js is a well-maintained and lightweight JavaScript library for simple performance monitoring. It is perfect for projects where monitoring speed is a priority. It’s a practical solution that easily integrates into existing JavaScript code.