Environment Variables

Lesson in the Next.js Roadmap · Stage 28: Environment Variables

Last updated 14 September 2026

What is Environment Variables?

Environment variables are dynamic values that can affect the behavior of programs on a computer. They are typically used to store configuration settings, API keys, and other sensitive information that should not be hardcoded directly into the application's source code. This allows you to easily change the application's behavior without modifying the code itself, making it more flexible and secure across different environments like development, testing, and production.

Next.js comes with built-in support for environment variables, which allows you to use .env to load environment variables, and bundle environment variables for the browser by prefixing with NEXT_PUBLIC_

Study this in the interactive course See the whole Next.js roadmap

Free resources to learn Environment Variables

Official docsHow to use environment variables in Next.js

Environment Variables: common questions

Can I learn Environment Variables in Hindi?

This lesson is written in English. Once you sign in, open it in the interactive course and ask the AI tutor to explain Environment Variables in Hindi or Hinglish. The tutor answers from this lesson’s own text, so it stays on the syllabus, and it runs on your own Google, OpenAI or Anthropic key.

Is this Environment Variables tutorial for beginners?

It is lesson 82 of 94 in the free Next.js roadmap, in stage 28, Environment Variables. If you are new to Next.js, start from stage 1 and come back here in order; if you already know the earlier stages, this lesson stands on its own.