I am trying to set and get environment variable in node js .I tried like this I create the test.js file And add this line

console.log(process.env.NODE_ENV);

Run like this

 set NODE_ENV=production&&node test.js

It gives me undefined

I am trying to set and get environment variable in node js .I tried like this I create the test.js file And add this line

console.log(process.env.NODE_ENV);

Run like this

 set NODE_ENV=production&&node test.js

It gives me undefined

• javascript
• node.js

• u can read this article medium./the-node-js-collection/… hope it will help – sayalok Commented Apr 23, 2019 at 7:49
• Try NODE_ENV=production node test.js – Héctor Valls Commented Apr 23, 2019 at 7:49
• 2 set creates shell variables, not environment variables. – Alnitak Commented Apr 23, 2019 at 7:51
• You can read this answer stackoverflow./a/57509175/11127383 – Daniel Danielecki Commented Aug 15, 2019 at 11:48
• You have to do EXPORT NODE_ENV instead of SET NODE_ENV – kta Commented Oct 4, 2020 at 3:18

3 Answers 3

NODE_ENV=production node test.js on linux and $env:NODE_ENV = 'production'; node test.js in powershell.

In addition to the accepted answer:

From nodejs docs

It is possible to modify this object, but such modifications will not be reflected outside the Node.js process.

So you can also do something like:

process.env.foo = 'bar';
console.log(process.env.foo);

Assigning a property on process.env will implicitly convert the value to a string.

process.env.test = null;
console.log(process.env.test);
// => 'null'

Note: There are some env variables which you can set only before any codes are executed.

Also note:

On Windows operating systems, environment variables are case-insensitive.

process.env.TEST = 1;
console.log(process.env.test);
// => 1

1. create a package.json file.
2. install the dotenv npm package

make a .env file in your root directory. 
//env 
NODE_ENV=development
PORT=8626
# Set your database/API connection information here
API_KEY=**************************
API_URL=**************************

Now if you want to call your port in any file or server.js it will be like this.

const port = process.env.PORT;
console.log(`Your port is ${port}`);