> For the complete documentation index, see [llms.txt](https://developers-apps-in-toss.toss.im/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers-apps-in-toss.toss.im/documentation/api-and-sdk-en/sdk/domains-api/environment/environment.deviceid.md).

# Environment.deviceId

> Functional API `getDeviceId`You can use the same feature with it as well.

### Feature description

It is the unique identifier of the device in use. It can be used to save device-specific settings, analyze logs, and distinguish multiple devices belonging to the same user.

It's a constant value, so you can read it directly without calling anything.

### Type

```ts
Environment.deviceId: string;
```

**Params**

None

**Response**

It's a string.

### Example code

```js
import { Environment } from "@apps-in-toss/web-framework";

console.log(Environment.deviceId);
```


---

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