How to optimize a ReactJS application's performance?

There are many ways through which one can optimize the performance of a React app, let’s have a look at some of them:

  • Using useMemo( ) -
    It is a React hook that is used for caching CPU-Expensive functions.
    Sometimes in a React app, a CPU-Expensive function gets called repeatedly due to re-renders of a component, which can lead to slow rendering.
    useMemo( ) hook can be used to cache such functions. By using useMemo( ), the CPU-Expensive function gets called only when it is needed.

  • Using React.PureComponent -
    It is a base component class that checks state and props of a component to know whether the component should be updated.
    Instead of using the simple React.Component, we can use React.PureComponent to reduce the re-renders of a component unnecessarily.

  • Maintaining State Colocation -
    This is a process of moving the state as close to where you need it as possible.
    Sometimes in React app, we have a lot of unnecessary states inside the parent component which makes the code less readable and harder to maintain. Not to forget, having many states inside a single component leads to unnecessary re-renders for the component.
    It is better to shift states which are less valuable to the parent component, to a separate component.

  • Lazy Loading -
    It is a technique used to reduce the load time of a React app. Lazy loading helps reduce the risk of web app performances to minimal.