# Formatting
You can customize how certain pieces of information are formatted by the SDK.
## Formatting Dates
Overriding the `DateFormatter` allows you to change the way dates are formatted in the application:
```kotlin
ChatUI.dateFormatter = object: DateFormatter {
private val dateFormat: DateFormat = SimpleDateFormat("dd/MM/yyyy")
private val timeFormat: DateFormat = SimpleDateFormat("HH:mm")
override fun formatDate(date: Date?): String {
date ?: return ""
return dateFormat.format(date)
}
override fun formatTime(date: Date?): String {
date ?: return ""
return timeFormat.format(date)
}
override fun formatRelativeTime(date: Date?): String {
date ?: return ""
// Return relative time like "Just now", "5 minutes ago"
}
override fun formatRelativeDate(date: Date): String {
// Return relative date like "Yesterday", "A day ago"
}
}
```
```java
ChatUI.setDateFormatter(new DateFormatter() {
private final DateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy");
private final DateFormat timeFormat = new SimpleDateFormat("HH:mm");
public String formatDate(Date date) {
// Provide a way to format the date
return dateFormat.format(date);
}
public String formatTime(Date date) {
// Provide a way to format the time
return timeFormat.format(date);
}
public String formatRelativeTime(Date date) {
// Return relative time like "Just now", "5 minutes ago"
}
public String formatRelativeDate(Date date) {
// Return relative date like "Yesterday", "A day ago"
}
});
```
## Formatting Durations
Overriding the `DurationFormatter` allows you to change the way durations are formatted in the application:
```kotlin
ChatUI.durationFormatter = object: DurationFormatter {
override fun format(durationInMillis: Int): String {
// Your custom duration formatting logic
}
}
```
```java
ChatUI.setDurationFormatter(new DurationFormatter() {
public String format(int durationInMillis) {
// Your custom duration formatting logic
}
});
```
## Formatting Channel Names
You can customize the way channel names are formatted by overriding the default `ChannelNameFormatter`:
```kotlin
ChatUI.channelNameFormatter = ChannelNameFormatter { channel, currentUser ->
channel.name
}
```
```java
ChatUI.setChannelNameFormatter((channel, currentUser) -> channel.getName());
```
## Formatting Message Previews
You can customize how message previews are formatted in channel lists by overriding the default `MessagePreviewFormatter`:
```kotlin
ChatUI.messagePreviewFormatter = MessagePreviewFormatter { channel, message, currentUser ->
// Return custom preview text for the message
message.text
}
```
```java
ChatUI.setMessagePreviewFormatter((channel, message, currentUser) -> {
// Return custom preview text for the message
return message.getText();
});
```
## Markdown
The SDK provides a standalone Markdown module `stream-chat-android-markdown-transformer` that contains `MarkdownTextTransformer` which is an implementation of `ChatMessageTextTransformer`. It uses the [Markwon](https://github.com/noties/Markwon) library internally.
```kotlin
ChatUI.messageTextTransformer = MarkdownTextTransformer(context)
```
```java
ChatUI.setMessageTextTransformer(new MarkdownTextTransformer(context));
```
If you use `MarkdownTextTransformer`, don't use `android:autoLink` attribute because it'll break the markdown [Linkify](https://noties.io/Markwon/docs/v4/linkify/) implementation.
Then the SDK will parse Markdown automatically:
| Markdown Input in the Message Composer | Message with Markdown in the Message List |
| -------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------- |
|  |  |
---
This page was last updated at 2026-04-17T17:33:30.497Z.
For the most recent version of this documentation, visit [https://getstream.io/chat/docs/sdk/android/v6/ui/formatting/](https://getstream.io/chat/docs/sdk/android/v6/ui/formatting/).