Microsoft Bing Speech API: Android Speech-to-Text Client Library & Sample

This repo contains the Android client library & samples for Speech-to-Text in the Microsoft Bing Speech API, an offering within Microsoft Cognitive Services, formerly known as Project Oxford.

The Client Library

The Speech To Text client library is a client library for Microsoft Bing Speech, Speech-to-text API.

The easiest way to consume the client library is to add the package from Maven Central Repository. To find the latest version of client library, go to, and search for "".

To add the client library dependency from build.gradle file, add the following line in dependencies.

dependencies {
    // Use the following line to include client library from Maven Central Repository
    // Change the version number from the result
    compile ''

    // Your other Dependencies...

To add the client library dependency from Android Studio: 1. From Menu, Choose File > Project Structure 2. Click on your app module 3. Click on Dependencies tab 4. Click "+" sign to add new dependency 5. Pick "Library dependency" from the drop down list 6. Type "" and hit the search icon from "Choose Library Dependency" dialog 7. Pick the Project Oxford client library that you intend to use. 8. Click "OK" to add the new dependency 9. Download the appropriate JNI library from this page and put into your project's directory app/src/main/jniLibs/armeabi/ or app/src/main/jniLibs/x86/.

The Sample

This sample demonstrates the following features using a wav file or external microphone input:

  • Short-form recognition
  • Long-form dictation
  • Recognition with intent


  • Android OS must be Android 4.1 or higher (API Level 16 or higher)
  • The speech client library contains native code. To use this sample in an emulator, make sure that your build variant matches the architecture (x86 or arm) of your emulator. However, due to the need of audio, using a physical device is recommended.

Build the sample

  1. First, you must obtain a Bing Speech API subscription key by following the instructions on our website.

  2. Start Android Studio and choose "Import project (Eclipse ADT, Gradle, etc.)" from the "Quick Start" options from Speech > SpeechToText > Android folder.

  3. A "Gradle Sync" dialog will pop-up, choose OK to continue downloading the latest tools.

  4. In Android Studio -> "Project" panel -> "Android" view, open file "SpeechRecoExample/res/values/strings.xml", and find the line "Please_add_the_subscription_key_here;". Replace the "Please_add_the_subscription_key_here" value with your subscription key string from the first step. If you cannot find the file "strings.xml", it is in folder "Samples_SpeechRecoExample_res_values_strings.xml".

  5. In Android Studio, select menu "Build > Make Project" to build the sample, and "Run" to launch this sample app.

Running the sample

In Android Studio, select menu "Run", and "Run app" to launch this sample app.

  1. In the application, press the button "Select Mode" to select what type of Speech would like to use.

  2. For modes where you would like both Speech recognition and Intent to work, you need to sign up Language Understanding Intelligent Service (LUIS) and set the key values in luisAppID and luisSubscriptionID from "Samples_SpeechRecoExample_res_values_strings.xml".

  3. To Start recognition, press the Start button.


We welcome contributions. Feel free to file issues and pull requests on the repo and we'll address them as we can. Learn more about how you can help on our Contribution Rules & Guidelines.

You can reach out to us anytime with questions and suggestions using our communities below:

This project has adopted the Microsoft Open Source Code of Conduct. For more information see the Code of Conduct FAQ or contact with any additional questions or comments.


All Microsoft Cognitive Services SDKs and samples are licensed with the MIT License. For more details, see LICENSE.

Sample images are licensed separately, please refer to LICENSE-IMAGE.

Developer Code of Conduct

Developers using Cognitive Services, including this client library & sample, are expected to follow the “Developer Code of Conduct for Microsoft Cognitive Services”, found at