Java tutorial
//package com.java2s; import java.io.File; import android.os.Environment; import android.os.StatFs; public class Main { public static long availableSDCard() { File path = Environment.getExternalStorageDirectory(); long availableSize = 0; if (path != null) { StatFs stat = new StatFs(path.getPath()); long blockSize = stat.getBlockSize(); long availableBlock = stat.getAvailableBlocks(); availableSize = availableBlock * blockSize; } return availableSize / (1024 * 1024); } }