Environment Variables

You can use environment variables to dynamically configure the Studio depending on what context it‘s in.

Note: Make sure you are using version 3.5.0 or later in order to make full use of environment variables.

Exposed variables

Environment variables prefixed with SANITY_STUDIO_ are automatically picked up by the Sanity CLI tool, development server and bundler.

Any found environment variables are available as process.env.SANITY_STUDIO_VARIABLE_NAME - even in browser code.

By requiring this SANITY_STUDIO prefix, we prevent unrelated (and potentially sensitive) environment variables from getting exposed to the browser bundle.

Static replacement

It is important to note that these variables are statically replaced during production. It is therefore necessary to always reference them using the full static string. For example, dynamic key access like process.env[key] will not work (they might be accessible this way in development, but will fail in production).

Similarly, logging or iterating over process.env will not give you consistent results in development and production - in production, process.env will be said to be undefined, as all the values are statically replaced during the build. In other words:

// In development:
const studioTitle = process.env.SANITY_STUDIO_TITLE

// In production:
const studioTitle = "the value of the env var"

Note that during a build, it will also replace these references appearing in JavaScript strings. This should be a rare case, but it can have unintended side effects. You may see errors like Missing Semicolon or Unexpected token. One way to work around this behavior is to break the string up with a Unicode zero-width space, e.g. 'process\u200b.env.SANITY_STUDIO_FOO'.

Keeping secret things secret

It is common practice to keep secret tokens and API keys as environment variables that are not checked into version control. This is a decent strategy for server-side applications where the runtime is protected. However, since the Studio is a client-side application, you will have to approach secrets differently. We recommend using the Sanity Secrets library that gives you hooks and UI components for handling secrets.

Make sure that your .env.local files are ignored by your version control system (usually git), and do not put sensitive information or keys into the .env files commited.

Loading variables from .env files

Sanity will read .env files by default and make its variables available for the development server, production builds, command line actions and similar. Note that you still have to follow the variable naming conventions mentioned above. We also support env loading priorities for situations where you want to differentiate between sharing certain variables in all environments and overwriting them for production builds.

.env               # loaded in all cases
.env.local         # loaded in all cases, ignored by git
.env.[mode]        # only loaded in specified mode
.env.[mode].local  # only loaded in specified mode, ignored by git

Also, Sanity uses dotenv-expand to expand variables out of the box. To learn more about the syntax, check out their docs.

Manually declared environment variables (outside of .env files) take precedence, overriding any values set in .env files.

Modes

By default, the build and deploy commands runs in production mode, while all other commands run in development mode. Other commands can be run in production mode by setting NODE_ENV to production (note that only this value is supported, for other modes, use SANITY_ACTIVE_ENV).

This means when running sanity build, it will load the environment variables from .env.production if there is one:

# .env.production
SANITY_STUDIO_TITLE=My Studio

In your app, you can render the title using process.env.SANITY_STUDIO_TITLE.

In some cases, you may want to run sanity build with a different mode to render a different title. You can overwrite the default mode used for a command by setting an environment variable named SANITY_ACTIVE_ENV. For example, if you want to build your studio for a staging mode:

SANITY_ACTIVE_ENV=staging sanity build

And create an .env.staging file:

# .env.staging
SANITY_STUDIO_TITLE=My Studio (staging)

Best practices

We encourage you to keep environment variables to a minimum, and not spread them throughout the code base. Common (and valid) use cases are things like configuration files.

To more easily be able to tell which environment variables are used, and keep things as tidy as possible, we recommend having a single file that re-exports environment variables to the rest of your code. For instance:

// src/environment.ts
export const myStudioTitle = process.env.SANITY_STUDIO_TITLE
export const myCompanyApiUrl = process.env.SANITY_STUDIO_COMPANY_API_URL

Similarly, plugins should generally never use environment variables directly - instead, they should take a configuration object which the user can then choose to pass environment variables to:

import {somePluginApiUrl} from './src/environment'

defineConfig({
  plugins: [
    // ...
    somePlugin({
      // process.env.SANITY_STUDIO_SOME_PLUGIN_API_URL
      apiUrl: somePluginApiUrl
    })
  ]
})

Differences from Vite

Sanity's environment variable behavior is heavily inspired by (and partially powered by) Vite. There is however one key difference:

Vite exposes environment variables under import.meta.env. While Sanity also lets you access them that way, we heavily recommend that you access them using process.env.

Using process.env allows us to expose the same variables to both the browser and Node.js/Node.js powered tools without too much work. It also eases cross-environment migrations, such as moving from the default Vite-based bundler to (for instance) an embedded setup inside of Next.js.

Programmatic usage

Should you want to reuse the environment variable handling in other contexts (your own scripts, or using a different bundler etc), you can import and utilize the getStudioEnvironmentVariables() method from sanity/cli:

import {getStudioEnvironmentVariables} from 'sanity/cli'

console.log(getStudioEnvironmentVariables())
// {SANITY_STUDIO_SOME_VAR: 'yourVariableValue'}

Note that .env files are not loaded by default when using this method. To do so, pass an envFile option:

import {getStudioEnvironmentVariables} from 'sanity/cli'

console.log(
  getStudioEnvironmentVariables({
    envFile: {
      mode: 'production',
      envDir: '/path/to/some-dotenv-root'
    }
  })
)

For usage in bundlers (such as Vite's define option or Webpacks DefinePlugin), you'll usually want the keys to be fully qualified with the process.env prefix, and the values to be JSON-encoded. The method can do all of this for you:

import {getStudioEnvironmentVariables} from 'sanity/cli'

console.log(
  getStudioEnvironmentVariables({
    jsonEncode: true,
    prefix: 'process.env.'
  })
)

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