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# userId$

> Observable of the participant's user ID.

```ts
get userId$(): Observable<string | undefined>
```

Observable of the participant's user ID.

## **Inherited from**

[`Participant`](/docs/browser-sdk/v4/reference/participant).[`userId$`](/docs/browser-sdk/v4/reference/participant#userid-1)

## userId

```ts
get userId(): string | undefined
```

User ID of this participant, or `undefined` if not available.

## **Inherited from**

[`Participant`](/docs/browser-sdk/v4/reference/participant).[`userId`](/docs/browser-sdk/v4/reference/participant#userid)

## **Examples**

```ts
selfParticipant.userId$.subscribe((userId) => {
  console.log('userId:', userId);
});
```

> Observable of the participant's user ID.