Language Understanding

A machine learning-based service for building natural language understanding into apps, bots and IoT devices. Quickly create enterprise-ready, custom models that continuously improve.

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LUIS application response


"Language understanding technology helps us bridge the gap between what people say and what they mean."

Alexander Mejia, Owner and Creative Director, Human Interact


Add natural language understanding to your apps

Designed to identify valuable information in conversations, Language Understanding interprets user goals (intents) and distils valuable information from sentences (entities), for a high-quality, nuanced language model. Language Understanding integrates seamlessly with the Speech service for instant Speech-to-Intent processing, and with the Azure Bot Service, making it easy to create a sophisticated bot.

Quickly build a custom language solution

Powerful developer tools are combined with customisable pre-built apps and entity dictionaries, such as Calendar, Music and Devices, so you can build and deploy a solution more quickly. Dictionaries are mined from the collective knowledge of the web and supply billions of entries, helping your model to correctly identify valuable information from user conversations.

Always learning and improving

Reinforcement learning is used to continuously improve the quality of the natural language processing models. Once the model starts processing input, Language Understanding begins active learning, allowing you to constantly update and improve the model.

Enterprise-ready, available worldwide

The service is ready to be deployed in commercial applications and can scale with enterprise quality and performance. The service meets international compliance standards and supports 12 languages, making it highly accessible.


"LUIS is very good at understanding people's intent, which was an important point for us. It also has a learning capability, which allows us to continually improve our service."

Daisuke Kezuka, General Manager of Travel Business, NAVITIME

Explore Language Understanding scenarios

Information ChatbotThis Informational Bot can answer questions defined in a knowledge set or FAQ using Cognitive Services QnA Maker and answer more open-ended questions using Azure Cognitive Search.AzureActive DirectoryAzureBot ServiceLanguageUnderstandingCustomer mobileConsume, PC, MobileCloud15AzureApp ServiceAzureApp Insights2StructuredAzure Search7634QnA MakerApplication bot
  1. Overview
  2. Flow

Information Chatbot


This Informational Bot can answer questions defined in a knowledge set or FAQ using Cognitive Services QnA Maker and answer more open-ended questions using Azure Cognitive Search.


  1. 1 Employee starts the Application Bot
  2. 2 Azure Active Directory validates the employee’s identity
  3. 3 The employee can ask the bot what type of queries are supported
  4. 4 Cognitive Services returns an FAQ built with the QnA Maker
  5. 5 The employee defines a valid query
  6. 6 The Bot submits the query to Azure Cognitive Search which returns information about the application data
  7. 7 Application insights gathers runtime telemetry to help development with Bot performance and usage
商用チャットボットAzure Bot Service と Language Understanding サービスを組み合わせることで、開発者は銀行、旅行、エンターテイメントなどのさまざまなシナリオに合わせた会話型のインターフェイスを作成できます。たとえば、ホテルのコンシェルジュは、ボットを使用して Azure Active Directory で顧客を認証し、Cognitive Services でテキストや音声を使用して顧客の要求を文脈から処理することで、従来の電子メールや電話でのやりとりを強化できます。音声認識サービスを追加すると、音声コマンドに対応できるようになります。1234567
  1. Overview
  2. Flow

Commerce Chatbot


Together, the Azure Bot Service and Language Understanding service enable developers to create conversational interfaces for various scenarios like banking, travel and entertainment. For example, a hotel’s concierge can use a bot to enhance traditional email and phone call interactions by validating a customer via Azure Active Directory and using Cognitive Services to better contextually process customer requests using text and voice. The speech recognition service can be added to support voice commands.


  1. 1 Customer uses your mobile app
  2. 2 Using Azure AD B2C, the user authenticates
  3. 3 Using the custom Application Bot, user requests information
  4. 4 Cognitive Services helps process the natural language request
  5. 5 Response is reviewed by customer who can refine the question using natural conversation
  6. 6 Once the user is happy with the results, the Application Bot updates the customer’s booking
  7. 7 Application insights gathers runtime telemetry to help development with Bot performance and usage
IoT デバイスインターネットに接続したテレビや冷蔵庫から発電所に至るまで、インターネットにアクセス可能なあらゆるデバイスに、シームレスな会話型インターフェイスを作成できます。LUIS なら、最大 500 個のインテントを統合して、コマンドを翻訳し、スマートなアクションを実行できます。Customer mobileConsume, PC, MobileCloud14IoT devicesThird party352AzureBot ServiceAzureApp ServiceAzureApp InsightsLanguageUnderstanding
  1. Overview
  2. Flow

IoT devices


Create seamless conversational interfaces with all of your Internet-accessible devices – from your connected television or fridge to devices in a connected power plant. LUIS is able to integrate up to 500 intents to translate commands into smart actions.


  1. 1 User logs in to Skype and accesses the IoT bot
  2. 2 Using voice, the user asks the bot to turn on the lights via the IoT device
  3. 3 The request is relayed to a third-party service that has access to the IoT device network
  4. 4 The results of the command are returned to the user
  5. 5 Application Insights gathers runtime telemetry to help development with bot performance and usage

"We determined that artificial intelligence could be the key to offering our customers the differentiated and personalized service and cohesive customer journey we're aiming for."

Antonia Colin-Jones, Strategic Partnership Programme Manager, Dixons Carphone

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Dixons Carphone

"Dynamics 365, as well as LUIS for interacting with the bot using natural language, are very intuitive and easy to use."

Melanie Sachse, Central Sales Development and Digitalization, VHV Allgemeine Versicherung AG

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VHV Allgemeine Versicherung AG

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