Java tutorial
//package com.java2s; import android.os.Environment; import android.os.StatFs; import java.io.File; public class Main { @SuppressWarnings("deprecation") public static long getAvailableExternalMemorySize() { if (externalMemoryAvailable()) { File path = Environment.getExternalStorageDirectory(); StatFs stat = new StatFs(path.getPath()); long blockSize = stat.getBlockSize(); long availableBlocks = stat.getAvailableBlocks(); return availableBlocks * blockSize; } else { return -1; } } public static boolean externalMemoryAvailable() { return android.os.Environment.getExternalStorageState().equals(android.os.Environment.MEDIA_MOUNTED); } }