Lately, I’ve noticed a lot of discussions about React (and SPAs in general) vs Next (server-side rendered websites in general). I decided to add my two cents because I genuinely believe that both of these are amazing technologies and very useful in practice. The key is to know their strength and use them for suitable use cases.
Next.js apps really excel when it comes to SEO and fast loading times. If it’s important for your website or application to perform well in search engines then you are probably better off for going with next JS. Server-side rendering is a SEO-friendly alternative to absolute build to purely in react.
In terms of speed, both have their advantages and disadvantages. The single-page applications so may take a little longer the first time they are rendered especially on devices with limited computing powers. This is because you’re rendering doesn’t happen on the server but in the client itself. Rendering is the most resource-intensive process when loading web applications.
On the other hand, the next JS applications receive already rendered pages from the server. This is reduced the load on the computer and increases the execution time. Once render the then single-page applications are faster than pages rendered on the server. The trick is that single-page applications already have all the information so when a user navigates from one page to another it’s like looking at different parts of the fuller picture. The initial load is loading the full picture.
React SPAs are better in a number of different ways. For example, there are many supporting libraries to build user interfaces. For example, create input elements with react-select library.
In summary that’s the difference in speed between the next JS apps and the react single page application apps. Even the name itself single page application SPA says that your browser is essentially loading just one page. Depending on different routes it shows different parts of that one page.
Another concern with a single-page applications built with React is their incompatibility with search engines. Because everything is rendered in the browser itself then search engines don’t have anything to index from your page. This is a great disadvantage if you want to get organic traffic from search engines for your pages. For example, if you’re running an online store you want to people to be able to find your products and the category pages in search engines. For that to happen, you have to use textJS or similar server-side rendered applications.
So to answer this question shortly which are better next JS or React. The answer is that both of their use cases and you can successfully use them both for certain use cases.