# User Avatar

User avatars on video calling screens are important for identifying users, creating a sense of presence, and expressing personality.
As such, it is important to be able to customise user avatars according to your app specifications.

![User Avatar](https://getstream.io/docs-assets/images/6c6a1ae36097.png)

## Customising the user avatar

The user avatar can be modified via the `userAvatarTheme` parameter of the `StreamCallParticipant` widget:

```dart
StreamCallContainer(
  // ...
  callContentWidgetBuilder: (
    BuildContext context,
    Call call,
  ) {
    return StreamCallContent(
      call: call,
      callParticipantsWidgetBuilder: (
        BuildContext context,
        Call call,
      ) {
        return StreamCallParticipants(
          call: call,
          callParticipantBuilder: (
            BuildContext context,
            Call call,
            CallParticipantState participantState,
          ) {
            return StreamCallParticipant(
              call: call,
              participant: participantState,
              userAvatarTheme: StreamUserAvatarThemeData(),
            );
          },
        );
      },
    );
  },
),
```

### Customising size of the avatar

You can change the size of the user avatar on the screen by providing it `BoxConstraints` using the constraints parameter.
The default value of the constraints is `BoxConstraints.tightFor(height: 40, width: 40)`.

```dart
StreamUserAvatarThemeData(
  constraints: const BoxConstraints.tightFor(
    height: 50,
    width: 50,
  ),
),
```

### Customising border radius of the avatar

You can change the border radius of the user avatar using the `borderRadius` parameter.
The default value for border radius is `20` units.

```dart
StreamUserAvatarThemeData(
  borderRadius: const BorderRadius.all(Radius.circular(25)),
),
```

### Changing the style of initials displayed

If the user does not have an image to be displayed, initials of the user are displayed instead.
To change the style of these initials, you can use the `initialsTextStyle` parameter:

```dart
StreamUserAvatarThemeData(
  initialsTextStyle: TextStyle(
    fontWeight: FontWeight.bold,
  ),
),
```


---

This page was last updated at 2026-08-10T16:01:02.637Z.

For the most recent version of this documentation, visit [https://getstream.io/video/docs/flutter/ui-components/utility/avatar/](https://getstream.io/video/docs/flutter/ui-components/utility/avatar/).