Create React App: using environment variables in index.html

reactjs create-react-app

32,125

Solution 1

I just tried with an (almost) new CRA setup and it works.

<head>
  <title>React App</title>
  <script type="text/javascript">
   console.log("%REACT_APP_TEST%") // OK
   console.log("%NODE_ENV%") // development
  </script>
</head>

Did you try restarting the server? I just tried changing the test variable with your example and it works if you restart the development server.

As someone pointed out in the comments, the official documentation of CRA has a section about that.

Solution 2

Make sure you restart your create-react-app when adding variables into the .env file

Also make sure you have >= [email protected]

I use .env variables for the meta title of a site with various language versions of the build:

<title>%REACT_APP_SITE_TITLE%</title>

Solution 3

From the docs (here):

make sure your react-scripts dependency version is equal or greater than 0.0.9
create a .env file at the same level of your package.json
make sure all you variables start with REACT_APP_; for example REACT_APP_TITLE
use them in you js / ts code using process.env.REACT_APP_XXX
or in you html code surrounding it with % ie <title>%REACT_APP_TITLE%</title>
restart your development server / re-compile your app when making changes to your .env file

Solution 4

I tried like this 'NODE_ENV=development npm start' and it works well

Solution 5

If you want environmental variable in script tag, put the variable in quote:

<script src="https://maps.googleapis.com/maps/api/js?key=%REACT_APP_MAP_API%&v=3.exp&libraries=places" async
    ></script>

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32,125

Author by

Colin Ricardo

https://github.com/colinricardo

Updated on February 17, 2022

Comments

Colin Ricardo about 2 years
Is there a way to inject environment variables, e.g. REACT_APP_MY_API into the index.html file?

According to this, it can be done, but I can't seem to get it to work.

.env
```
REACT_APP_MY_API=https://something.com
```
index.html
```
<script type="text/javascript">
  console.log("%REACT_APP_MY_API%") // undefined 
  console.log("%NODE_ENV%") // development
</script>
```
Colin Ricardo over 5 years

Very strange, I had restarted and it still wasn't working. Working now, thanks!
Ritesh almost 4 years

Thanks a lot.. it saved my hours of R&D..!!
SajithK about 3 years

This is only applied at build time.