Fix Next.js Error: window is not defined (2025 Guide)
Fix Next.js Error: window is not defined (2025 Guide) Fix Next.js Error: window is not defined (2025 Guide) Posted on: April 15, 2025 Encountered an "Error: window is not defined" in Next.js? This error occurs when you try to access the `window` object during server-side rendering or static site generation. Let’s fix it fast in this 2025 guide! What Causes "Error: window is not defined"? This error happens because Next.js renders pages on the server where `window` (a browser-specific object) is unavailable. Common causes include: Direct Window Access : Using `window` in a component or function without checking the environment. Third-Party Libraries : Libraries that assume a browser context. Dynamic Imports Missing : Failing to use client-side only imports. ...