diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5287f80..8235986 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,6 @@
+## 0.4.9
+* fix the power calculation for android
+
 ## 0.4.8
 * Fix version number in .podspec
 
diff --git a/android/src/main/java/com/zeno/flutter_audio_recorder/FlutterAudioRecorderPlugin.java b/android/src/main/java/com/zeno/flutter_audio_recorder/FlutterAudioRecorderPlugin.java
index fc6325c..f452df4 100644
--- a/android/src/main/java/com/zeno/flutter_audio_recorder/FlutterAudioRecorderPlugin.java
+++ b/android/src/main/java/com/zeno/flutter_audio_recorder/FlutterAudioRecorderPlugin.java
@@ -5,7 +5,6 @@
 import android.media.AudioFormat;
 import android.media.AudioRecord;
 import android.media.MediaRecorder;
-import android.os.Environment;
 import android.os.SystemClock;
 import android.support.v4.app.ActivityCompat;
 import android.support.v4.content.ContextCompat;
@@ -18,9 +17,7 @@
 import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.nio.ByteOrder;
-import java.util.Date;
 import java.util.HashMap;
-import java.util.concurrent.TimeUnit;
 
 import io.flutter.plugin.common.MethodCall;
 import io.flutter.plugin.common.MethodChannel;
@@ -336,15 +333,15 @@ private void resetRecorder(){
   }
 
   private void updatePowers(byte[] bdata){
-    double max=0;
-    double sum=0;
     short[] data = byte2short(bdata);
-    for(int i=0; i<data.length; i++){
-      max = Math.max(Math.abs(data[i]), max);
-      sum += Math.abs(data[i]);
+    short sampleVal = data[data.length - 1];
+    if(sampleVal == 0){
+      mAveragePower = -160;
     }
-    mPeakPower = max;
-    mAveragePower = sum / data.length;
+    else {
+      mAveragePower = 20 * Math.log(Math.abs(sampleVal) / 32768.0);
+    }
+    mPeakPower = mAveragePower;
     Log.d(LOG_NAME, "Peak: " + mPeakPower + " average: "+ mAveragePower);
   }
 
diff --git a/example/pubspec.lock b/example/pubspec.lock
index 8ec046d..f2717b1 100644
--- a/example/pubspec.lock
+++ b/example/pubspec.lock
@@ -68,7 +68,7 @@ packages:
       path: ".."
       relative: true
     source: path
-    version: "0.4.7"
+    version: "0.4.8"
   flutter_test:
     dependency: "direct dev"
     description: flutter
diff --git a/pubspec.yaml b/pubspec.yaml
index 4e1c193..770b6c4 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,6 +1,6 @@
 name: flutter_audio_recorder
 description: Flutter Audio Record Plugin that supports Record Pause Resume Stop and provide access to audio level metering properties average power peak power.
-version: 0.4.8
+version: 0.4.9
 authors:
   - wenyan <nik.lee.nyc@gmail.com>
   - tao zhu <tao@zeno.group>