Fix Next.js Slow Page Load and Performance Issues at Scale (2025 Guide)

Posted on: April 13, 2025

Experiencing slow page load or performance issues at scale in Next.js? This problem can arise due to inefficient rendering, large datasets, or server-client waterfalls. Let’s optimize it fast in this 2025 guide!

What Causes Slow Page Load and Performance Issues in Next.js?

Performance issues in Next.js often occur when handling large-scale applications or traffic. Common causes include:

• Inefficient Data Fetching: Slow API calls or large datasets in `getServerSideProps` or `getStaticProps`.
• Overuse of SSR: Excessive server-side rendering for every request.
• Client-Server Waterfall: Unnecessary rehydration or redundant requests.

Here’s a Next.js example that may cause slow performance:

// This may cause slow page load due to inefficient rendering
export async function getServerSideProps() {
  // Simulate a slow API call with large data
  const res = await fetch('https://api.example.com/large-dataset');
  const data = await res.json();
  return { props: { data } };
}

export default function Page({ data }) {
  return (
    

      {data.map((item) => (
        

          
{item.title}
          
{item.description}
        
      ))}
    
  );
}

Running this with a large dataset or slow API can lead to noticeable delays.

How to Fix It: 3 Solutions

Let’s optimize performance with practical steps:

(Diagram: Developer identifies slow load, optimizes rendering, improves performance.)

Solution 1: Use Incremental Static Regeneration (ISR)

Switch to ISR to reduce server load and improve performance:

export async function getStaticProps() {
  const res = await fetch('https://api.example.com/large-dataset');
  const data = await res.json();
  return {
    props: { data },
    revalidate: 60, // Revalidate every 60 seconds
  };
}

export default function Page({ data }) {
  return (
    

      {data.map((item) => (
        

          
{item.title}
          
{item.description}
        
      ))}
    
  );
}

ISR caches static pages and regenerates them periodically, reducing SSR overhead.

Solution 2: Optimize Data Fetching with Edge Functions

Use Edge Functions or cache API responses to speed up data fetching:

// pages/api/data.js
export default async function handler(req, res) {
  const cachedData = await fetch('https://api.example.com/large-dataset', {
    cache: 'force-cache',
  });
  const data = await cachedData.json();
  res.status(200).json(data);
}

// Use in getServerSideProps
export async function getServerSideProps() {
  const res = await fetch('http://localhost:3000/api/data');
  const data = await res.json();
  return { props: { data } };
}

export default function Page({ data }) {
  return (
    

      {data.map((item) => (
        

          
{item.title}
          
{item.description}
        
      ))}
    
  );
}

Edge caching minimizes server-client waterfalls and speeds up responses.

Solution 3: Implement React Server Components (RSC)

Use React Server Components to offload rendering to the server efficiently:

'use server'; // Mark as Server Component

async function DataComponent({ data }) {
  const items = await data; // Fetch or process data on server
  return (
    

      {items.map((item) => (
        

          
{item.title}
          
{item.description}
        
      ))}
    
  );
}

export default async function Page() {
  const res = await fetch('https://api.example.com/large-dataset');
  const data = await res.json();
  return ;
}

RSC reduces client-side rendering load and improves initial page load times.

Quick Checklist

• Overusing SSR? (Switch to ISR)
• Slow API calls? (Use Edge Functions or caching)
• Client-side heavy? (Implement React Server Components)

Conclusion

Slow page load and performance issues at scale in Next.js can be addressed with ISR, caching, and React Server Components. With these 2025 optimizations, your app’s performance will soar. Got another Next.js challenge? Let us know in the comments!