How to Fix Dynamic Server Usage Error in Next.js

The dynamic server usage error in Next.js happens when you use server-only APIs or code inside a client component. To fix it, move server-side code to a server component or API route and keep client components free of server-only logic by adding "use client" at the top of client files.

Why This Happens

This error occurs because Next.js separates server and client components. Server components can use server-only features like database calls or environment variables. Client components run in the browser and cannot access these server-only features. If you try to use server code inside a client component, Next.js throws a dynamic server usage error.

javascript

"use client";

import { getServerSideData } from '../lib/serverData';

export default function MyComponent() {
  const data = getServerSideData(); // This is server-only code
  return <div>{data.message}</div>;
}

Output

Error: You’re importing a server-only module in a client component.

The Fix

To fix this, separate server and client code. Move server-only logic to a server component or API route. Mark components that run in the browser with "use client" at the top. Fetch server data in server components or via API calls, then pass it down as props to client components.

javascript

// Server component (no "use client")
import { getServerSideData } from '../lib/serverData';

export default async function MyServerComponent() {
  const data = await getServerSideData();
  return <MyClientComponent data={data} />;
}

// Client component
"use client";

export function MyClientComponent({ data }) {
  return <div>{data.message}</div>;
}

Output

<div>Server data message displayed here</div>

Prevention

Always mark components that use browser features with "use client". Keep server-only code like database queries or environment variables inside server components or API routes. Use Next.js linting rules to catch improper imports. Structure your app to clearly separate server and client logic to avoid this error.

Related Errors

• Invalid Hook Call: Happens if React hooks are used in server components.
• Module Not Found: Occurs if server-only modules are imported incorrectly in client code.
• Hydration Mismatch: Caused by differences between server and client rendered output.

Key Takeaways

Mark client components with "use client" to separate client and server code.

Keep server-only logic inside server components or API routes.

Pass server data as props to client components instead of importing server code directly.

Use Next.js linting to detect improper server-client imports early.

Clear separation of server and client code prevents dynamic server usage errors.