How to Optimize Your ReactJS Site for Google's Core Web Vitals

If you're using ReactJS to build your website or web application, you'll want to ensure that it's optimized for Google's Core Web Vitals. Google's Core Web Vitals are a set of metrics that measure the performance of a web page. They include things like loading time, interactivity, and stability. Optimizing your ReactJS site for these metrics ensures that your site will perform well in search results and provide a better user experience.

• Use React.lazy and Suspense to lazy-load components.
• Use React memoization to memoize expensive calculations.
• Use React.Suspense to suspend rendering until critical resources have been loaded.

1. Use React.lazy and Suspense to lazy-load components

Lazy loading is a technique that allows you to load a component only when needed. This can improve the initial loading time of your website by avoiding unnecessary component loads. React provides a built-in way to lazy-load components using React.lazy and Suspense.

React.lazy allows you to load a component only when needed. It takes a function that returns a promise as an input and a lazy-loaded component version. The following example lazy-loads the MyComponent component:

const MyComponent = React.lazy(() => import('./MyComponent'));

Suspense lets you specify what should happen while a component is loaded, which can improve the user experience. The following example renders a loading indicator while the MyComponent component is being loaded:

const MyComponent = React.lazy(() => import('./MyComponent'));

function App() {
  return (
    <div>
      <Suspense fallback={<div>Loading...</div>}>
        <MyComponent />
      </Suspense>
    </div>
  );
}

2. Use React memoization to memoize expensive calculations.

Memoization is a technique that allows you to cache the results of expensive calculations and reuse them when needed. This can improve the performance of your website by avoiding unnecessary calculations. React provides a built-in way to memoize calculations using the useMemo hook.

The following example shows how to use the useMemo hook to memoize anexpensive calculation:

function expensiveCalculation(n) {
  // Expensive calculation here
}


function App() {
  const n = useMemo(() => expensiveCalculation(10), []);
  return <div>{n}</div>;
}

3. Use React.Suspense to suspend rendering until critical resources have been loaded

This can improve loading time and reduce the number of resources used by your website. React provides a built-in way tosuspend rendering using the Suspense component. The following example suspends rendering until the MyComponent component has been loaded:

const MyComponent = React.lazy(() => import('./MyComponent'));
function App() {
  return (
    <div>
      <Suspense fallback={<div>Loading...</div>}>
        <MyComponent />
      </Suspense>
    </div>
  );
}

Conclusion

Following these optimization tips ensures that your ReactJS site is well-optimized for Google's Core Web Vitals. This will improve your site's performance in search results and provide a better user experience.