Language detection and dynamic machine translation in Virtual Agent standard chat conversations

Language detection and machine translation work together in Virtual Agent to improve the chat experience for users across languages. You can designate fallback languages for locales or dynamically translate languages that aren't professionally localized or aren't supported in topic discovery.

Why enable language detection and dynamic translation

Chat users are more comfortable having conversations in their preferred language. Their preferred language is set in the user's profile language preference. For example, Virtual Agent greets users in the preferred language specified in their user profile. If a user responds in another language, Virtual Agent can detect the change. Depending on your user experience, users either receive a prompt regarding whether they'd like to switch the conversational language to the detected language or the conversational language updates automatically to the detected language. After the language is switched to the detected language, that language becomes the conversation's language for the remainder of the conversation. Often, users don't have control over their preferred language, particularly if they are guest users.

Guest conversations don't support language detection if resumable guest sessions aren't enabled. Language detection and dynamic machine translation can still improve the chat experience for languages your organization hasn't authored topic content in. For example, your organization may routinely translate topic content into Spanish and French, but you can also enable Dynamic Translation on your ServiceNow® instance to support additional languages, such as Dutch and Danish, without authoring separate content for each one.

You can use language detection to support custom or locale-specific language codes as well. For example, topic discovery doesn't support Mexican Spanish (es-mx), but it does support Spanish (es). You can designate Spanish as the fallback language for Mexican Spanish, ensuring that these users have a good customer experience.

Note: You can use language detection independently of Dynamic Translation.

How dynamic translation resolves and caches text

Virtual Agent conversations can be dynamically translated. Virtual Agent uses platform translations and if no platform translations are found, then Dynamic Translation is used instead. If some conversations have been professionally translated, disable dynamic translation for those specific languages. Professional translations of topics may be more accurate than machine translations. Before making a dynamic translation call, the Text Translations for Dynamic Translation [sys_cs_dynamic_translation_text] and Message [sys_ui_message] tables are checked to see if the text has been previously translated or already has a localization record. A dynamic translation call is only made if no translation exists in either table. After a dynamic translation call is made and that text is translated, that translated text is stored in the Text Translations for Dynamic Translation [sys_cs_dynamic_translation_text] table for future use. This table is cleared every 24 hours to ensure that the most up-to-date translations stored in the Message [sys_ui_message] table are being referenced. Storing previously translated text results in fewer dynamic translation calls to third-party translation services. For more information about localizing Virtual Agent conversations, see (Legacy) Localizing Virtual Agent NLU conversations.

You can use Dynamic Translation during the localization process as well. If you are localizing conversations with professional linguists, you can enable Dynamic Translation while some topics and strings remain untranslated. When your deployment in that language is complete, you can disable Dynamic Translation, since professional translations are likely more accurate.

[Omitted image "icon-video-link.png"] Alt text: Video link Virtual Agent Academy: Dynamically translate languages in Virtual Agent Watch this video for a demonstration of using Virtual Agent with Dynamic Translation.

Language detection and Dynamic Translation process

When you enable language detection and Dynamic Translation for Virtual Agent for other languages, a variety of diverse users gain access to your Virtual Agent chat environment.

Language detection is only applicable to the first utterance entered into the conversation. Conversational language switching cannot occur mid-conversation. Language detection prompts users with a question regarding whether they'd like to switch the conversational language during Virtual Agent LLM standard chat conversations.

When language detection is turned off, no conversational language switching can occur.

The default system language sets all users' default session language. That user's default session language is what sets the conversational language. When a user types an utterance that is not recognized as the system language, the results depend upon your configuration for that language.

The following examples show how a conversational language can be impacted depending upon the language detection and dynamic translation settings:

Language configuration	Results in Virtual Agent LLM standard chat conversations
Language detection and Dynamic Translation aren't configured.	For topics that haven't been translated into other languages, the language they appear in depends on the language they were authored in. Typically, the default system language is used for topics and topic discovery.
Language detection is enabled, but not Dynamic Translation	Language responses can show up differently depending on whether those topics have been translated. The conversation language may continue in the detected language if translated content for those topics already exists. If translated content doesn't exist, the conversation continues in the preferred conversational language. If the detected language is a locale or other language code that has been configured with a fallback language, Virtual Agent asks the user if they want to switch the conversation to the fallback language. For example, if the detected language is Mexican Spanish (mx-es), and Spanish (es) has been designated as the fallback language, Virtual Agent asks: `I have detected you are typing in Spanish. Would you like to switch the conversation to Spanish? (Yes/No)` If the user selects Yes, the fallback language is used for topic discovery and topic display. This continues until the conversation ends. If the user selects No, Virtual Agent does not prompt them again during the conversation.
Language detection and Dynamic Translation are enabled	If the detected language is enabled for dynamic translation in Virtual Agent Chat Settings, Virtual Agent asks the user if they want to switch the conversation to the detected language. For example, the preferred conversational language is in English but the user types an utterance in Spanish. The user receives a prompt asking whether they'd like to switch the conversation to Spanish. The prompt reads, `I have detected you're typing in Spanish. Would you like to switch the conversation to Spanish? (Yes/No)` If the user selects No, Virtual Agent does not prompt them again during the conversation and the conversation continues in English. If the user selects Yes, the user prompt is translated to the default language. The default language for LLM conversations is within the com.glide.cs.llm.default.Language system property. All topic matches are translated dynamically into the user's conversation language and displayed. In this example, the conversation continues in Spanish and Virtual Agent expects the user to continue chatting in Spanish. After the conversation ends and the user restarts a new conversation by reloading their browser or initially navigating to a portal with no conversation in progress, the prior conversational language (Spanish in this example) continues.

Language configuration

Results in Virtual Agent LLM standard chat conversations

Language detection and Dynamic Translation aren't configured.

For topics that haven't been translated into other languages, the language they appear in depends on the language they were authored in. Typically, the default system language is used for topics and topic discovery.

Language detection is enabled, but not Dynamic Translation

Language responses can show up differently depending on whether those topics have been translated. The conversation language may continue in the detected language if translated content for those topics already exists. If translated content doesn't exist, the conversation continues in the preferred conversational language.

If the detected language is a locale or other language code that has been configured with a fallback language, Virtual Agent asks the user if they want to switch the conversation to the fallback language.

For example, if the detected language is Mexican Spanish (mx-es), and Spanish (es) has been designated as the fallback language, Virtual Agent asks: I have detected you are typing in Spanish. Would you like to switch the conversation to Spanish? (Yes/No)

If the user selects Yes, the fallback language is used for topic discovery and topic display. This continues until the conversation ends.

If the user selects No, Virtual Agent does not prompt them again during the conversation.

Language detection and Dynamic Translation are enabled

If the detected language is enabled for dynamic translation in Virtual Agent Chat Settings, Virtual Agent asks the user if they want to switch the conversation to the detected language.

For example, the preferred conversational language is in English but the user types an utterance in Spanish. The user receives a prompt asking whether they'd like to switch the conversation to Spanish. The prompt reads, I have detected you're typing in Spanish. Would you like to switch the conversation to Spanish? (Yes/No)

If the user selects No, Virtual Agent does not prompt them again during the conversation and the conversation continues in English.

If the user selects Yes, the user prompt is translated to the default language. The default language for LLM conversations is within the com.glide.cs.llm.default.Language system property. All topic matches are translated dynamically into the user's conversation language and displayed. In this example, the conversation continues in Spanish and Virtual Agent expects the user to continue chatting in Spanish. After the conversation ends and the user restarts a new conversation by reloading their browser or initially navigating to a portal with no conversation in progress, the prior conversational language (Spanish in this example) continues.

\[Omitted image "nava-lang-detect-updated-buttons.png"\] Alt text: Virtual Agent detects an utterance in Spanish and asks the user if they want to switch, in both English and Spanish.

The language detection and dynamic machine translation process operates according to the following principles:

Language detection occurs only once per conversation, at the initial utterance.

If a user tries to change the language in the middle of a conversation, Virtual Agent returns an I didn't understand message.
After the conversation closes and restarts, the language used in the next conversation varies depending on how the user restarted the conversation. If the user restarts the conversation by reloading the browser, the preferred language is restored in the next conversation. If the user restarted the conversation by using the chat widget's restart feature, the previous conversational language is restored in the next conversation. Regardless of how a conversation has closed and restarted for standard chat conversations, if a user did not accept to switch languages after a different language was detected in the previous conversation, the preferred language is restored in the next conversation.
If a user's detected language is the same as the preferred language, the user is not asked to switch languages.
If a user's detected language has no fallback language specified and dynamic translation is not enabled for it, the conversation continues in the preferred language.
If a user's detected language is not activated on the instance, the conversation continues in the preferred language. For more information, see Activate a language.

Note: If you create exclusion rules for Dynamic Translation, those excluded terms are honored during Dynamic Translation. For more information about the Exclusion Framework, see Exclusion Framework in Dynamic Translation.

For more information on enabling language detection, see Enable Dynamic Translation for languages in Virtual Agent. For more information on enabling dynamic translation, see Configure multilingual service for ServiceNow Otto applications.

Note: AI Search results aren't translated.

Dynamic Translation and Agent Chat

If Dynamic Translation is enabled on Virtual Agent but turned off for Agent Chat, the live agent sees what the user sees. If the user started the conversation in another language and the conversational language switches, then the live agent will see the conversation in the user's detected language. This may cause some confusion for both the agent and the customer. To resolve this issue, consider turning on Dynamic Translation for Agent Chat as well. For details, see Configuring Dynamic Translation for Agent Chat.

Supported languages

Install the ServiceNow language plugins for each language that uses dynamic translation. For a detailed list of language plugins, see Activate a language.

You can enable dynamic translation for languages that aren't currently supported on the ServiceNow platform. For details, see Enable Dynamic Translation for an unsupported language.

Supported channels

Dynamic Translation for Virtual Agent is currently supported in the following channels:

ServiceNow chat widget
Microsoft Teams
Slack

Note: The Virtual Agent topic test window may identify user inputs from Microsoft Teams or other adapters as sysparm_search_text. Dynamic Translation will translate this content as well.

The following channels don't support Dynamic Translation for Virtual Agent:

ServiceNow mobile client
WhatsApp
Twilio SMS

title	Language detection and dynamic machine translation in Virtual Agent standard chat conversations
description	Language detection and machine translation work together in Virtual Agent to improve the chat experience for users across languages. You can designate fallback languages for locales or dynamically translate languages that aren't professionally localized or aren't supported in topic discovery.
locale	en-US
canonical_url	https://www.servicenow.com/docs/r/conversational-interfaces/virtual-agent/dynamic-lang-detection-translation-standard-chat-nlu.html
release	brazil
product	Virtual Agent
classification	virtual-agent
topic_type	concept
last_updated	2026-09-10
reading_time_minutes	9
breadcrumb	Translate conversationsVirtual AgentConversational Interfaces