Sometimes, we want to fix window is not defined in Next.js React app.

In this article, we’ll look at how to fix window is not defined in Next.js React app.

How to fix window is not defined in Next.js React app?

To fix window is not defined in Next.js React app, we check if window is undefined.

For instance, we write

if (typeof window !== "undefined") {
  // ...
}

to check if window isn’t undefined.

If it’s not, then we can run client side code safely by putting the code in the if block.

Conclusion

To fix window is not defined in Next.js React app, we check if window is undefined.