Fix Flutter: Android SDK Version Warning (Step-by-Step)

Nov 28, 2025 by Alex Johnson 56 views

Fixing the "Android SDK Version" Warning in Flutter: A Step-by-Step Guide

Encountering warnings during your Flutter builds can be frustrating, especially when they hint at SDK version conflicts. One common issue is the "Android SDK version" warning, often triggered by plugins requiring a higher SDK version than your project is configured to use. This comprehensive guide walks you through understanding and resolving this warning, ensuring a smooth development experience.

Understanding the Android SDK Version Warning

The warning message, typically resembling the one below, indicates a mismatch between the SDK version required by a plugin (in this case, flutter_plugin_android_lifecycle) and the compileSdk version set in your project's build.gradle file.

Warning: The plugin flutter_plugin_android_lifecycle requires Android SDK version 36 or higher.
For more information about build configuration, see https://flutter.dev/to/review-gradle-config.
Your project is configured to compile against Android SDK 35, but the following plugin(s) require to be compiled against a higher Android SDK version:
- flutter_plugin_android_lifecycle compiles against Android SDK 36
Fix this issue by compiling against the highest Android SDK version (they are backward compatible).
Add the following to /workspace/android/app/build.gradle:
    android {
        compileSdk = 36
        ...
    }

In essence, this warning means:

A Flutter plugin you're using needs a newer Android SDK.
Your project is set to compile against an older SDK.
To fix it, you need to update your project's compileSdk version.

Why does this happen?

Plugins often leverage features and APIs available in specific Android SDK versions. When a plugin requires a newer SDK, your project needs to be configured to compile against that version or higher to ensure compatibility. Android SDKs are backward-compatible, so targeting a higher SDK version generally doesn't break compatibility with older Android devices.

Step-by-Step Solution: Updating Your `compileSdk` Version

The recommended solution is to update your project's compileSdk to the highest Android SDK version your Flutter environment supports. Here's how to do it:

1. Locate the `build.gradle` File

The file you need to modify is located in the android/app/ directory of your Flutter project. Open your project in your preferred code editor and navigate to this directory. You'll find a file named build.gradle. This is the Gradle build file specific to your Android application module.

2. Open the `build.gradle` File

Open the build.gradle file in your code editor. This file contains various configuration settings for your Android app, including the compileSdk version.

3. Find the `android` Block

Within the build.gradle file, locate the android block. This block is where Android-specific configurations are defined. It typically looks like this:

android {
    // Configurations here
}

4. Modify the `compileSdk` Version

Inside the android block, you'll find the compileSdk property. This property specifies the Android SDK version your project is compiled against. To resolve the warning, you need to update this value to the SDK version required by the plugin (or a higher version). In the example warning, the flutter_plugin_android_lifecycle plugin requires SDK version 36 or higher. So, you'd change the compileSdk value to 36.

android {
    compileSdk = 36 // Update this line
    // Other configurations
}

Important: It's generally recommended to use the latest stable Android SDK version available in your Flutter environment. You can check the latest version in your Android Studio SDK Manager or by referring to the official Android documentation.

5. Sync Gradle

After modifying the build.gradle file, you need to sync Gradle to apply the changes. In Android Studio, you can do this by clicking on the "Sync Now" link that appears in the top-right corner of the editor, or by going to File > Sync Project with Gradle Files.

This will trigger Gradle to re-evaluate the project configuration and download any necessary dependencies for the new SDK version.

6. Clean and Rebuild Your Project

To ensure that the changes are fully applied, it's a good practice to clean and rebuild your Flutter project. You can do this using the following Flutter commands in your terminal:

flutter clean
flutter build apk // Or flutter build appbundle

flutter clean removes the build artifacts, forcing a full rebuild. flutter build apk (or flutter build appbundle) builds your Android app with the new configuration.

Additional Considerations and Best Practices

1. `targetSdkVersion` and `minSdkVersion`

While updating compileSdk is crucial for resolving plugin compatibility issues, it's also essential to consider the targetSdkVersion and minSdkVersion properties in your build.gradle file.

targetSdkVersion: This specifies the API level that your app is designed to run on. It's recommended to set this to the latest stable Android SDK version to take advantage of new features and improvements.
minSdkVersion: This specifies the minimum Android API level that your app supports. Setting this too high will exclude users with older devices. It's important to balance supporting a wide range of devices with leveraging newer APIs.

android {
    compileSdk = 36
    
    defaultConfig {
        // ...
        minSdkVersion 21 // Example: Minimum Android 5.0 (Lollipop)
        targetSdkVersion 33 // Example: Target Android 13 (Tiramisu)
        // ...
    }
    // ...
}

2. Managing Dependencies

Keeping your dependencies up-to-date is crucial for a healthy Flutter project. Regularly check for updates to your plugins and libraries in your pubspec.yaml file.

Run flutter pub outdated in your terminal to see which dependencies have newer versions available.

3. Resolving Conflicts

In some cases, updating the compileSdk might introduce conflicts with other dependencies or plugins. If you encounter such issues, carefully review the error messages and consult the documentation for the affected dependencies. You might need to update other dependencies or adjust your code to resolve the conflicts.

4. Using Android Studio's SDK Manager

Android Studio provides a convenient SDK Manager for installing and managing Android SDK versions. You can access it through Tools > SDK Manager. Ensure you have the necessary SDK versions installed for your project's compileSdk, targetSdkVersion, and minSdkVersion.

5. Checking Flutter Doctor

Flutter's flutter doctor command is a valuable tool for diagnosing issues in your Flutter environment. Run this command in your terminal to check for missing dependencies, outdated tools, or other potential problems.

Example `build.gradle` Snippet

Here's an example of how your android/app/build.gradle file might look after updating the compileSdk and considering targetSdkVersion and minSdkVersion:

android {
    compileSdk = 36

    namespace "your.package.name" // Replace with your actual package name

    defaultConfig {
        applicationId "your.package.name" // Replace with your actual package name
        minSdkVersion 21
        targetSdkVersion 33
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
    }

    buildTypes {
        release {
            signingConfig signingConfigs.debug
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
    kotlinOptions {
        jvmTarget = '1.8'
    }
    sourceSets {
        main.java.srcDirs += 'src/main/kotlin'
    }
}

dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:\$kotlin_version"
}

Conclusion

The "Android SDK version" warning in Flutter is a common issue that can be easily resolved by updating your project's compileSdk version. By following the steps outlined in this guide, you can ensure that your project is compatible with the plugins you're using and leverage the latest Android features. Remember to also consider targetSdkVersion and minSdkVersion for optimal app compatibility and performance. Keeping your dependencies up-to-date and regularly checking your Flutter environment with flutter doctor will further contribute to a smoother development workflow.

For more in-depth information on Android SDK versions and Gradle configuration, refer to the official Android developer documentation on the Android Developers website.