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Load .env into React Native - with support for multiple .env files.
Load .env into React Native with import statements. A Babel plugin that inlines your environment variables at build time — with multi-environment support.
Install it.
npm install react-native-dotenv --save-dev
Add it to your Babel config:
// babel.config.js module.exports = function (api) { api.cache(false) return { plugins: [ ['module:react-native-dotenv'] ] } }
Create a .env file in the root of your project:
# .env HELLO="Dotenv" API_URL=https://api.example.org
Import your environment variables:
// App.js import { HELLO, API_URL } from '@env' console.log(`Hello ${HELLO}`) fetch(`${API_URL}/users`)
That's it. Your environment variables from .env are available via @env!
◇ injected env (2) from .env
with the dotenv CLI
Use dotenv v18's dotenv run command when you want the same environment variables available to build tooling and your app's @env imports. The Babel plugin still inlines values into the app at build time.
Install dotenv directly so your package manager makes its CLI available to your project scripts:
npm install --save-dev dotenv@^18.0.1
Select a file when starting Metro:
{
"scripts": {
"start:staging": "dotenv run -f .env.staging -- react-native start --reset-cache"
}
}# .env.staging API_URL=https://staging.example.org
Keep the Babel plugin configured as shown in Usage, then import normally:
import { API_URL } from '@env' fetch(`${API_URL}/users`)
The CLI loads the selected file into the process environment before Metro starts. Existing shell/CI values win unless you pass --override to dotenv run. The plugin then gives non-empty process environment values priority over its own .env files.
The plugin still loads its usual files; -f selects the CLI's file, not the plugin's path or APP_ENV. This can change precedence: plain dotenv run loads .env into the process environment, so those values win over the plugin's .env.local values. Use the CLI when you intend its injected values to take priority.
With the default safe: false, keys loaded only by the CLI work through @env imports. With safe: true, those keys must also appear in files the plugin reads. Likewise, process.env.X is only inlined for keys in the plugin's files (plus NODE_ENV, BABEL_ENV, and envName).
Stop Metro and rerun the script after changing CLI-loaded values; its process environment is set at startup. The script resets Metro's cache when restarting.
The CLI is optional. For values used only by app code, the Babel plugin can continue loading .env files on its own.
// babel.config.js module.exports = function (api) { api.cache(false) return { presets: ['babel-preset-expo'], plugins: [ ['module:react-native-dotenv'] ] } }
# .env HELLO="Universe"
// app/index.tsx import { HELLO } from '@env' import { Text } from 'react-native' export default function HomeScreen() { return <Text>Hello {HELLO}</Text> }
Then start with a clean Metro cache: npx expo start --clear.
envName (default: 'APP_ENV')Override which environment variable selects the mode file (separate from NODE_ENV). Metro can overwrite the test environment even if you specify a config, so this gives you a dedicated override.
// package.json { "scripts": { "start:staging": "APP_ENV=staging npx react-native start" } }
The above example would use the .env.staging file.
To use your own name:
{
"plugins": [
["module:react-native-dotenv", {
"envName": "MY_ENV"
}]
]
}// package.json { "scripts": { "start:staging": "MY_ENV=staging npx react-native start" } }
Note: if you're using APP_ENV (or envName), you cannot use development nor production as values, and you should avoid having a .env.development or .env.production. This is a Babel and Node thing that I have little control over unfortunately and is consistent with many other platforms that have an override option, like Gatsby. If you want to use development and production, you should not use APP_ENV (or envName), but rather the built-in NODE_ENV=development or NODE_ENV=production or you can just use debug vs release modes. It actually does compile but only for the start command so it is up to you but then you have to run react-native start every time you change the values.
moduleName (default: '@env')The module name used in import statements.
import { HELLO } from '@env'
For TypeScript or Next.js it is often advised to set moduleName to react-native-dotenv.
{
"plugins": [
["module:react-native-dotenv", {
"moduleName": "react-native-dotenv"
}]
]
}path (default: '.env')Path to the base env file.
{
"plugins": [
["module:react-native-dotenv", {
"path": ".env"
}]
]
}allowlist (default: null)Limit imports to only these env variable names.
{
"plugins": [
["module:react-native-dotenv", {
"allowlist": [
"HELLO",
"API_URL"
]
}]
]
}blocklist (default: null)Prevent these env variable names from being imported.
{
"plugins": [
["module:react-native-dotenv", {
"blocklist": [
"GITHUB_TOKEN"
]
}]
]
}safe (default: false)Only allow variables defined in your .env files. Host environment variables can still override values for those same keys at build time, but keys that exist only in the environment (and not in .env) are not imported.
{
"plugins": [
["module:react-native-dotenv", {
"safe": true
}]
]
}When using safe mode, it's highly recommended to set allowUndefined to false.
allowUndefined (default: true)Allow importing undefined variables; their value will be undefined.
{
"plugins": [
["module:react-native-dotenv", {
"allowUndefined": true
}]
]
}import { UNDEFINED_VAR } from '@env' console.log(UNDEFINED_VAR === undefined) // true
When set to false, an error will be thrown.
verbose (default: false)Also print the active dotenv mode to stderr while transforming.
{
"plugins": [
["module:react-native-dotenv", {
"verbose": true
}]
]
}quiet (default: false)Suppress the stderr inject message (◇ injected env (N) from .env).
{
"plugins": [
["module:react-native-dotenv", {
"quiet": true
}]
]
}You can also use process.env — the plugin inlines matching keys at build time the same way.
console.log(`Hello ${process.env.HELLO}`) fetch(`${process.env.API_URL}/users`)
process.env.X is only inlined when X is in your .env files (plus NODE_ENV / BABEL_ENV / envName). That keeps build-tooling noise out of the bundle without special-casing tool names.
For host/CI-only values, use @env imports — or put the key in .env and let CI override the value.
This package now supports environment specific variables. This means you may now import environment variables from multiple files, i.e. .env, .env.development, .env.production, and .env.test. This is based on dotenv-flow.
Note: it is not recommended that you commit any sensitive information in .env file to code in case your git repo is exposed. The best practice is to put a .env.template or .env.development.template that contains dummy values so other developers know what to configure. Then add your .env and .env.development to .gitignore. You can also keep sensitive keys in a separate .env.local (and respective .env.local.template) in .gitignore and you can use your other .env files for non-sensitive config.
If you are publishing your apps on an auto-publishing platform like EAS (Expo Application Services), make sure to put your secrets on the platform dashboard directly. If you are wondering what environment the platforms choose it is likely .env.production (not .env.prod) and there is likely no way to change this.
The base set of variables will be .env and the environment-specific variables will overwrite them.
The variables will automatically be pulled from the appropriate environment and development is the default. The choice of environment is based on your Babel environment first and if that value is not set, your NPM environment, which should actually be the same, but this makes it more robust.
In general, Release is production and Debug is development.
To choose, setup your scripts with NODE_ENV for each environment
// package.json { "scripts": { "start:development": "NODE_ENV=development npx react-native start", "start:production": "NODE_ENV=production npx react-native start" } }
Prefer Zod to validate your env and infer types — no hand-written env.d.ts needed.
import { z } from 'zod' export const env = z.object({ HELLO: z.string().min(1), API_URL: z.string().url() }).parse({ HELLO: process.env.HELLO, API_URL: process.env.API_URL }) console.log(`Hello ${env.HELLO}`) fetch(`${env.API_URL}/users`)
env is fully typed from the schema. If a value is missing or invalid, Zod throws at startup instead of failing later in production.
If you are not familiar with how dotenv or Babel work, make sure to read the following reference materials:
This Babel plugin processes your .env files and your environment variables and replaces the references to the environment variables in your code before it runs. This is because the environment variables will no longer be accessible once the React Native engine generates the app outputs.
When using with babel-loader with caching enabled you will run into issues where environment changes won’t be picked up.
This is due to the fact that babel-loader computes a cacheIdentifier that does not take your .env file(s) into account. The good news is that a recent update has fixed this problem as long as you're using a new version of Babel. Many react native libraries have not updated their Babel version yet so to force the version, add in your package.json:
"resolutions": { "@babel/core": "^7.20.2", "babel-loader": "^8.3.0" }
If this does not work, you should set api.cache(false) in your babel config, which resets Babel cache.
If you're using android, add a clean task to your run command: react-native run-android --tasks clean,installDebug
metro.config.jsresetCache: true
You can easily clear the cache:
rm -rf node_modules/.cache/babel-loader/*or reset all caches
npm start -- --reset-cache
or
yarn start --reset-cache
or
yarn start --clear
or
jest --no-cache
or
expo r -c
and
expo start --clear
or
react-native clean
or
rm -rf .expo/web/cache
or
Maybe a solution for updating package.json scripts:
"cc": "rimraf node_modules/.cache/babel-loader/*,", "android": "npm run cc && react-native run-android", "ios": "npm run cc && react-native run-ios",
Or you can override the default cacheIdentifier to include some of your environment variables.
The tests that use require('@env') are also not passing.
For nextjs, you must set moduleName to react-native-dotenv.
How does this work?
This Babel plugin reads your .env files at build time and replaces @env imports (and matching process.env references) with their values before the React Native bundle is generated. Runtime Node process.env is not available in the app the same way.
No. Values are inlined into your JavaScript bundle. Anyone who unpacks your app can read them. Only put public config in .env — keep real secrets on a server.
Yes. Set moduleName to react-native-dotenv (Next.js already owns @env).
{
"plugins": [
["module:react-native-dotenv", {
"moduleName": "react-native-dotenv"
}]
]
}Use dotenvx.
Should I commit my `.env` file?No.
Unless you encrypt it with dotenvx. Then we recommend you do.
Can I use `process.env` instead?Yes. The plugin inlines matching keys at build time the same way as @env imports.
console.log(`Hello ${process.env.HELLO}`) fetch(`${process.env.API_URL}/users`)
We recommend creating one .env file per environment. Use .env for local/development, .env.production for production and so on. This still follows the twelve factor principles as each is attributed individually to its own environment. Avoid custom set ups that work in inheritance somehow (.env.production inherits values from .env for example). It is better to duplicate values if necessary across each .env.environment file.
In a twelve-factor app, env vars are granular controls, each fully orthogonal to other env vars. They are never grouped together as “environments”, but instead are independently managed for each deploy. This is a model that scales up smoothly as the app naturally expands into more deploys over its lifetime.
Additionally, we recommend using dotenvx to encrypt and manage these.
This package also supports dotenv-flow-style files (.env, .env.local, .env.<mode>, .env.<mode>.local). See Multi-env under Advanced.
Use dotenvx to unlock syncing encrypted .env files over git.
Usually cache. Clear Metro/Babel cache and restart:
npm start -- --reset-cache # or yarn start --reset-cache # or expo start --clear
Also set api.cache(false) in your Babel config (see Usage), or clear node_modules/.cache/babel-loader/*. See Caching under Advanced for more.
Remove it, remove git history and then install the git pre-commit hook to prevent this from ever happening again.
npm i -g @dotenvx/dotenvx
dotenvx precommit --install
Babel/Node treat development and production specially. If you use APP_ENV (or envName), avoid those values — use something like staging / release instead. Prefer built-in NODE_ENV=development / NODE_ENV=production when you need those modes. See envName under Advanced.
@env is a virtual module created by this Babel plugin — it is not an npm package. Make sure module:react-native-dotenv is in your Babel config, restart Metro with a cache reset, and that your moduleName option matches the import (default @env).
Prefer Zod to validate and infer types — see Types with Zod under Advanced.
What happens to environment variables that were already set?By default, we will never modify any environment variables that have already been set. In particular, if there is a variable in your .env file which collides with one that already exists in your environment, then that variable will be skipped (the existing value wins at build time).
process.env.X is only inlined when X appears in a .env file. Host/CI-only keys still work via import { X } from '@env'.
See CHANGELOG.md
These npm modules depend on it.
Projects that expand it often use the keyword "dotenv" on npm.
Long maintained by Kemal Ahmed (@goatandsheep).