Older React apps built with Create React App look for the REACT_APP_ prefix.
The primary purpose of .env.local is to , ensuring that secrets and local URLs do not leak into your version control system. Why Use .env.local ?
If you want, I can:
You might wonder why we need multiple .env files. Here are the three primary reasons: 1. Local Overrides .env.local
Check these common culprits:
Why .env and .env.local Are Crucial – A DEV Community post that breaks down the "why" behind the two-file system.
Understanding .env.local: The Developer’s Personal Vault If you’ve ever worked on a modern web project—whether it’s Next.js, Vite, or a Node.js backend—you’ve likely seen a .env file. But as projects grow, so does the need for environment-specific configurations. Enter . Older React apps built with Create React App
Next.js has the most sophisticated environment variable handling. It supports multiple files out-of-the-box.
In Next.js specifically, .env.local is a first-class citizen with built-in support. The framework automatically loads this file (along with other .env* variants) into process.env , making your variables instantly available throughout your application.
loadEnv overrides content from .env(.mode)?.local ... - GitHub If you want, I can: You might wonder why we need multiple
: Avoid spaces around the equals sign. Write KEY=value , not KEY = value . Spaces can cause frameworks to misinterpret the string.
// What you write: const url = process.env.NEXT_PUBLIC_API_URL;