Loads environment variables from .env file


Dotenv loads environment variables from .env into ENV (process.env).

"Storing configuration in the environment is one of the tenets of a twelve-factor app. Anything that is likely to change between deployment environments–such as resource handles for databases or credentials for external services–should be extracted from the code into environment variables.

But it is not always practical to set environment variables on development machines or continuous integration servers where multiple projects are run. Dotenv loads variables from a .env file into ENV when the environment is bootstrapped."

Brandon Keepers' Dotenv in Ruby

npm install dotenv --save

As early as possible in your application, require and load dotenv.


Create a .env file in the root directory of your project. Add environment-specific variables on new lines in the form of NAME=VALUE. For example:


That's it.

process.env now has the keys and values you defined in your .env file.

  host: process.env.DB_HOST,
  username: process.env.DB_USER,
  password: process.env.DB_PASS

config will read your .env file, parse the contents, and assign it to process.env - just like load does. You can additionally, pass options to config.

Note: config and load are synonyms. You can pass options to either.

Default: .env

You can specify a custom path if your file containing environment variables is named or located differently.

require('dotenv').config({path: '/custom/path/to/your/env/vars'});

Default: utf8

You may specify the encoding of your file containing environment variables using this option.

require('dotenv').config({encoding: 'base64'});

The engine which parses the contents of your file containing environment variables is available to use. It accepts a String or Buffer and will return an Object with the parsed keys and values.

var dotenv  = require('dotenv');
var buf    = new Buffer('BASIC=basic');
var config  = dotenv.parse(buf); // will return an object 
console.log(typeof config, config) // object { BASIC : 'basic' } 

The parsing engine currently supports the following rules:

  • BASIC=basic becomes {BASIC: 'basic'}
  • empty lines are skipped
  • lines beginning with # are treated as comments
  • empty values become empty strings (EMPTY= becomes {EMPTY: ''})
  • single and double quoted values are escaped (SINGLE_QUOTE='quoted' becomes {SINGLE_QUOTE: "quoted"})
  • new lines are expanded if in double quotes (MULTILINE='new\nline' becomes
  • inner quotes are maintained (think JSON) (JSON={"foo": "bar"} becomes {JSON:"{\"foo\": \"bar\"}")

Basic variable expansion is supported.


Parsing that would result in {BASIC: 'basic', TEST: 'basic'}. You can escape variables by quoting or beginning with \ (e.g. TEST=\$BASIC). If the variable is not found in the file, process.env is checked. Missing variables result in an empty string.

TEST=example node -e 'require("dotenv").config();'
  • process.env.BASIC would equal basic
  • process.env.TEST would equal example
  • process.env.DNE would equal ""

No. We strongly recommend against committing your .env file to version control. It should only include environment-specific values such as database passwords or API keys. Your production database should have a different password than your development database.

See Contributing Guide

Here's just a few of many repositories using dotenv: