Last Edit: Jan 14 2021

Chat messages can be translated on-demand or automatically, this allows users speaking different languages on the same channel.

Message Translation Endpoint

This API endpoint translates an existing message to another language. The source language is inferred from the user language or detected automatically by analysing its text. If possible it is recommended to store the user language, see "Set user language" section later in this page.

await channel.sendMessage({
  id: messageID,
  text: "Hello, I would like to have more information about your product."}

// returns the message.text translated into French
const response = await client.translateMessage(messageID, "fr");

// the translation will be added to the i18n object
// "Bonjour, J'aimerais avoir plus d'informations sur votre produit.",

await channel.sendMessage(Message(
  id: messageId,
  text: 'Hello, I would like to have more information about your product.',
// returns the message.text translated into French 
final response = await channel.translateMessage(messageId, 'fr');

// the translation will be added to the i18n object
// "Bonjour, J'aimerais avoir plus d'informations sur votre produit.",

let channel = .messaging, id: "general")
let message = Message(text: "Hello, I would like to have more information about your product.")
// Send the message, so it has a valid id
channel.send(message: message) { result in
    let message = result.value!.message
    // Translate the message into French
    message.translate(to: .french) { (result) in
        let translatedMessage = result.value!.message
        // "Bonjour, J'aimerais avoir plus d'informations sur votre produit.",

ChannelController channelController ="messaging:general");
Message message = new Message();
message.setText("Hello, I would like to have more information about your product.");
channelController.sendMessage(message).enqueue(result -> {
    Message message1 =;
    String messageId = message1.getId();

    client.translate(messageId, "fr").enqueue(result1 -> {
        Message translatedMessage =;

        String frenchText = translatedMessage.getI18n().get("fr");

        return Unit.INSTANCE;

    return Unit.INSTANCE;

val channelController ="messaging:general")
val message = Message(text = "Hello, I would like to have more information about your product.")
val frenchLanguage = "fr"
channelController.sendMessage(message).enqueue { result ->
    val messageId =
    client.translate(messageId, frenchLanguage).enqueue { result ->
        val translatedMessage =
        val translation = translatedMessage.getTranslation(frenchLanguage)

The endpoint returns the translated message, updates it and sends a message.updated event to all users on the channel.

Only the text field is translated, custom fields and attachments are not included.

Available Languages

Language name Language code
Afrikaans af
Albanian sq
Amharic am
Arabic ar
Azerbaijani az
Bengali bn
Bosnian bs
Bulgarian bg
Chinese (Simplified) zh
Chinese (Traditional) zh-TW
Croatian hr
Czech cs
Danish da
Dari fa-AF
Dutch nl
English en
Estonian et
Finnish fi
French fr
French (Canada) fr-CA
Georgian ka
German de
Greek el
Hausa ha
Hebrew he
Hindi hi
Hungarian hu
Indonesian id
Italian it
Japanese ja
Korean ko
Latvian lv
Malay ms
Norwegian no
Persian fa
Pashto ps
Polish pl
Portuguese pt
Romanian ro
Russian ru
Serbian sr
Slovak sk
Slovenian sl
Somali so
Spanish es
Spanish (Mexico) es-MX
Swahili sw
Swedish sv
Tagalog tl
Tamil ta
Thai th
Turkish tr
Ukrainian uk
Urdu ur
Vietnamese vi

i18n data

When a message is translated, the i18n object is added. The i18n includes the message text in all languages and the code of the original language.

The i18n object has one field for each language named using this convention language-code_text

Here is an example after translating a message from english into French and Italian.

    "fr_text": "Bonjour, J'aimerais avoir plus d'informations sur votre produit.",
    "it_text": "Ciao, vorrei avere maggiori informazioni sul tuo prodotto.",
    "language": "en"

Automatic translation

Automatic translation translates all messages immediately when they are added to a channel and are delivered to the other users with the translated text directly included.

Automatic translation works really well for 1-1 conversations or group channels with two main languages.

Let's see how this works in practice:

  1. A user sends a message and automatic translation is enabled

  2. The language set for that user is used as source language (if not the source language will be automatically detected)

  3. The message text is translated into the other language in used on the channel by its members

When using auto translation, it is recommended setting the language for all users and add them as channel members

Enabling automatic translation

Automatic translation is not enabled by default. You can enable it for your application via API or CLI. You can also enable auto translation on a channel basis.

// enable auto-translation only for this channel
await channel.update({auto_translation_enabled: true});

// ensure all messages are translated in english for this channel
await channel.update({
   auto_translation_enabled: true,
   auto_translation_language: "en",

// auto translate messages for all channels
await client.updateAppSettings({auto_translation_enabled: true});

Set user language

In order for auto translation to work, you must set the user language or specify a destination language for the channel using the auto_translation_language field (see previous code example).

// sets the user language
await client.setUser({id, language: "en"})

// watch a channel
await"messaging", "melting-pot")
Messages are automatically translated from the user language that posts the message to the most common language in use by the other channel members.

Caveats and limits

  • Translation is only done for messages with up to 5,000 characters. Blowin' In The Wind from Bob Dylan contains less than 1,000 characters

  • Error messages and commands are not translated (ie. /giphy hello)

  • When a message is updated, translations are recomputed automatically

  • Changing translation settings or user language have no effect on messages that are already translated