# environment > Check which JavaScript environment your code is running in at runtime ## Install ```sh npm install environment ``` ## Usage ```js import {isBrowser, isNode} from 'environment'; if (isBrowser) { console.log('Running in a browser!'); } if (isNode) { console.log('Running in Node.js!'); } ``` > [!NOTE] > Runtime checks should be used sparingly. Prefer [conditional package exports](https://nodejs.org/api/packages.html#conditional-exports) and [imports](https://nodejs.org/api/packages.html#subpath-imports) whenever possible. ## API ### `isBrowser` Check if the code is running in a web browser environment. ### `isNode` Check if the code is running in a [Node.js](https://nodejs.org) environment. ### `isBun` Check if the code is running in a [Bun](https://bun.sh) environment. ### `isDeno` Check if the code is running in a [Deno](https://deno.com) environment. ### `isElectron` Check if the code is running in an [Electron](https://www.electronjs.org) environment. ### `isJsDom` Check if the code is running in a [jsdom](https://github.com/jsdom/jsdom) environment. ### `isWebWorker` Check if the code is running in a [Web Worker](https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API#worker_global_contexts_and_functions) environment, which could be either a dedicated worker, shared worker, or service worker. ### `isDedicatedWorker` Check if the code is running in a [Dedicated Worker](https://developer.mozilla.org/en-US/docs/Web/API/DedicatedWorkerGlobalScope) environment. ### `isSharedWorker` Check if the code is running in a [Shared Worker](https://developer.mozilla.org/en-US/docs/Web/API/SharedWorkerGlobalScope) environment. ### `isServiceWorker` Check if the code is running in a [Service Worker](https://developer.mozilla.org/en-US/docs/Web/API/ServiceWorkerGlobalScope) environment. ### `isMacOs` Check if the code is running on macOS. ### `isWindows` Check if the code is running on Windows. ### `isLinux` Check if the code is running on Linux. ### `isIos` Check if the code is running on iOS. ### `isAndroid` Check if the code is running on Android. ## Related - [is-in-ci](https://github.com/sindresorhus/is-in-ci) - Check if the process is running in a CI environment - [is64bit](https://github.com/sindresorhus/is64bit) - Check if the operating system CPU architecture is 64-bit or 32-bit - [is](https://github.com/sindresorhus/is) - Type check values