There are several tools available to check the performance of a ReactJS app. Here are some popular ones:
React Profiler: React Profiler is a built-in tool in the React Developer Tools extension for Chrome and Firefox. It helps you analyze the performance of your React components and identify performance bottlenecks. You can use it to measure the render time, identify slow-rendering components, and optimize your code.
React Performance: React Performance is a package that provides a set of tools to measure and improve the performance of your React application. It includes tools like the React DevTools profiler, the React Profiler, and the React Testing Library. You can use it to analyze the performance of your components, identify and fix performance issues, and improve the overall performance of your app.
Lighthouse: Lighthouse is an open-source tool that helps you improve the performance, accessibility, and SEO of your web application. It generates a report that includes performance metrics like first contentful paint, time to interactive, and other performance metrics. You can use it to identify performance issues and optimize your app for faster loading times.